Bryophytes
(EA-PS. William Campbell Steere)
BRYOPHYTES
CONTENTS
|
|
Page
|
|
Classes of Bryophytes
|
3
|
|
Musci
|
4
|
|
Spagna
|
6
|
|
Hepaticae
|
8
|
|
Anthocerotes
|
9
|
|
Distribution of Arctic and Subarctic Bryophytes
|
9
|
|
Arctic Alaska and the Yukon
|
10
|
|
Canadian Western Arctic
|
11
|
|
Canadian Eastern Arctic
|
12
|
|
Greenland
|
13
|
|
Iceland
|
14
|
|
Spitsbergen
|
15
|
|
Jan Mayen
|
15
|
|
Northern Scandinavia
|
16
|
|
Franz Josef Archipelago
[:
]
|
17
|
|
Severnaya Zemlya Archipelago
|
17
|
|
Soviet Arctic Mainland
|
17
|
|
General Considerations
|
18
|
|
Bryophyte Associations in the Arctic
|
22
|
|
Problems in Arctic Bryology
|
24
|
EA-Plant Sciences
(William Campbell Steere)
BRYOPHYTES
Mosses and liverworts (bryophytes) are small plants that as individuals
would scarcely be noticed. However, since they usually grow in tufts or mats,
they contribute much, in the aggregate, to the green color of forests, moun–
tains, and moors, especially in rainy weather. The association of mosses with
moist habitats is no accident, since none of these plants has true roots, and
they can, therefore, get little water from below the surface of the soil.
They need abundant moisture not only for their ordinary vegetative growth,
but also for their reproduction. Although a few mosses are able to live on
rocks exposed to the sun in deserts, and may not receive water more than a
few times a year, the great majority of them grow in moist places, and it is
very obvious to any observer that the moister the climate, the more abundant
are the mosses and liverworts.
In mountain forests where clouds hang low at night, or where mist and
rain are of almost continual occurrence, so that the air is saturated with
moisture during at least part of each day, mosses become so conspicuous that
this type of vegetation is known to botanists and to geographers as a special
type, the “mossy forest.” Mossy forests are found on the coastal ranges of
the Pacific Northwest of North America, where mosses clothe the trees and hang
from them in festoons, and may even become weeds in fruit orchards. In the wet
forests of tropical mountain peaks, mosses are so abundant that the apparent
diameter of tree trunks is doubled by their growth, and even the leaves may be
covered with liverworts and mosses. In arctic regions, where there are no
EA-PS
Steere: Bryophytes
forests, the abundance of mosses clothing rocks and ledges is directly related
to the amount of precipitation and humidity.
Mosses are very hardy plants and can resist extremely unfavorable condi–
tions. As one ascends a high mountain, he finds mosses and liverworts cover–
ing the rocks and the ground long after the disappearance of trees, and these
plants which appear so delicate have been collected at altitudes as great as
18,000 feet above sea level in the Himalayas and in the Andes of South America.
Likewise, as one goes north in Europe, Asia, and North America, he finds that,
in many areas beyond the tree line, mosses may become the most conspicuous land
plants, as well as the most numerous in species. For this reason, they are
among the very few plants which flourish on the Antarctic Continent.
A curious and interesting fe
^
a
^
ture of mosses is that the plants will revive
when moistened, ever after years of drought. Cells from leaves dried care–
fully for many years, when well soaked up, cannot be distinguished easily
under the microscope from fresh ones. The question as to whether or not these
old dried leaves are still alive has never been answered.
The ability of mosses to withstand not only low temperatures but also
desiccation means that they can invade freshly exposed rock surfaces, which
they gradually break down into soil, thereby preparing the way for larger
plants. This ability also enables them to grow as far northward as land goes,
to beyond 83° N. latitude on the northern end of Greenland, where temperatures
are very low in winter but relatively high in summer, where there
[:
]
is no
night during part of the year and no day during another part, and where they
are frozen solid for several mo
^
n
^
ths and then perhaps dried out during part of
the summer.
EA-PS
Steere: Bryophytes
Although all these conditions do not prevail on the summits of high
mountains, there is nevertheless some basis for comparing alpine and arctic
regions, especially since many species grow in both places. One of the best
analyses has been made recently by Meylan (67) who says (translated): “The
bryological vegetation of Iceland, especially that of the regions situated
at some altitude, seems analogous to that of the alpine meadows of our own
Alps, especially to that of the little snowy valleys in siliceous areas.
Much affinity is found likewise with our high altitude bogs. The carpet of
mosses in Iceland seems to develop, even more than in the Alps, brown and
purple coloration.
“Even though the rigorous climate of Iceland seems to cause an especially
vigorous development of some species, these conditions provoke in
[:
]
the major–
ity of species a diminution of growth and the formation of depauperate forms.
This phenomenon is especially visible in Hylocomium. One sees that these
species lack the shelter of the forest.
“The same phenomenon is observed as one ascends the Alps in the nival
zone, and one may note the same causes producing the same effects, a perfect
parallelism between these depauperate forms of arctic regions and those of the
elevated regions of our Alps. It is possible to present numerous examples
of this parallelism; I cite for the Acrocarpae only the Syntrichia, especially
S. ruralis
. In general, in Iceland, as at 3000 meters altitude in the Alps, the
stems of this species scarcely reach 1 to 1.5 cm.; the shorter leaves are no
longer squarrose, but erect like those of
S. montana
.”
Classes of Bryophytes
Mosses and liverworts fall into several groups, on the basis of structure
and reproductive behavior. The four classes are: (
1
) the true mosses, Musci;
EA-PS
Steere: Bryophytes
(
2
) the peat mosses, Sphagna; (
3
) the true liverworts,Hepaticae; and (
4
) the
hornworts, Anthocerotes.
Musci
. True mosses are always green, and therefore are all able to make their
own food. The individual plants range insize from nearly invisible to the naked
eye to more than a yard long, and consist of a creeping, hanging, floating, or
erect stem, covered with delicate, scalelike leaves. Mosses have no true roots
and must, therefore, depend for water absorption on small, threadlike tubes, the
rhizoids, that absorb moisture from the surface of the soil or from the atmos–
phere. For this reason, mosses are able to grow more or less continuo
o
^
u
^
sly through
the winter, when temperatures at midday rise to the thawing point, since they
can use a superficial film of water not available to the roots of higher plants
frozen fast in the ground. Most of the water used by mosses passes up the out–
side of the stem, by capillarity, through and over the layer of rhizoids which
covers the stem, and the height of an erect moss stem is apparently determined
by the height to which water will rise by capillary action.
In the
[:
]
tropical and temperate mossy forests, water is obtained from
the saturated air, so that banners of mosses a yard long, hanging from the
twigs and branches of trees, are not uncommon. Likewise, mosses growing in run–
ning water may develop very elongated stems which steam out for a yard or so
with the current. In contrast to the wet foresttypes, arctic mosses usually
have rather short stems because of the generally reduced rainfall and the drying
winds. The leaves of almost all mosses are only one layer of cells thick, in
striking contrast to the complex leaves of higher plants, which are usually
well-protected against evaporation, but which are killed at once if dried.
Mosses do not produce seeds, but much simpler, single-celled reproductive
bodies, the spores. The spores are very small and very light, so
^
that
^
they float in
EA-PS
Steere: Bryophytes
the atmosphere with only a slight movement of air, and have therefore been found
at very high altitudes in samples of air taken by airplanes. Each moss plant
produces hundreds of spores, and when one consider
[:
]
^
s
^
the large numbers of indi–
vidual plants of weedy species of mosses, he begins to realize the astronomical
numbers of spores released into the air during any one year. The spores may
live for years in some mosses, but in others they die almost at once if they
do not land in a suitable spot, just as with the seeds of higher plants. Moss
spores, however, need light for germination.
Mosses need water for fertilization, since the sperms are free-swimming,
just as in algae and in ferns. From the fertilized egg comes the spore-bearing
structure of a moss, consisting primarily of a usually cylindrical spore case,
supported on a threadlike stalk, embedded at its lower end in the green plant
from which it derives its moisture more or less parasit
u
^
i
^
cally. Although mosses
depend on water for their
[:
]
ordinary life processes, and water is indispensable
for fertilization, mosses do live mostly on land and often in relatively dry
places. The other great advance of mosses over algae, in an evolutionary sense,
is their conspicuous development of alternation of generations, in which a
spore-bearing plant, the sporophyte, with a diploid chromosome number, lives
dependently on the gamete-producing leafy green plant, which has a single set
of chromosomes. The obligate alternation of generations, with periodic doubling
and halving of chromosome number, is found in all higher plants.
Long-lived perennial mosses will produce a new set of sporophytes each
year and hundreds of spores, so that the persistence of most species is assured.
Other mosses, however, such as those which develop in summer on the mud flats
along receding rivers, may complete their whole life cycle in a few weeks. The
green plants appear, produce simple spore cases which break open and distribute
EA-PS
Steere: Bryophytes
the spores on the mud ready for another favorable season. Such annual mosses
are rather rare and so small that they are difficult to
[:
]
find, supporting the
common belief that mosses are delicate and short-lived plants. Some mosses
rarely produce spores, and this situation is especially pronounced in the
Arctic. Propagation is carried on by the production of detachable buds which
are carried about by wind, water, or other agencies. The method of reproduction
of many arctic mosses is completely unknown.
Sphagna
. Peat mosses, all belonging to the genus
Sphagnum
, of which perhaps
100 species exist in the whole world, are among the most absorbent of all plants,
since their leaves consist of large, bubble-like, dead, water-storage cells
which alternate with the narrow, green, living cells. The stems and branches
likewise contain special water-storage cells. These large and empty cells re–
flect light and cause peat mosses to appear white when dry, so that one who knows
peat moss about the greenhouse or garden is apt not to recognize it in the bog
when it is green, healthy, and filled with water. The absorbent powers of
Sphagnum
are so great that it is used to hold moisture in dry soils, to root
cuttings, to pack seedlings and cuttings for shipment, and even to ship clams
and other aquatic animals which otherwise die in the absence of water.
[:
]
Sphagnum
possesses another curious property in addition to its great
absorptiveness — it prevents the growth of many bacteria, and is, therefore,
somewhat antiseptic. For this reason it was used in enormous quantities during
World War I for filling absorbent bandages, because of a cotton shortage. A
striking demonstration of the antiseptic properties of
Sphagnum
and of the peat
that it produces is that people and animals who have fallen into bogs in Ireland
have been found rather perfectly preserved, perhaps hundreds of years later, upon
EA-PS
Steere: Bryophytes
the draining of the bog and cutting peat into blocks for fuel.
The tips of the peat-moss plants grow each year and branch, so that a tufted
growth is produced. As the plants grow upward, the deposit of dead material
below them, or peat, is made deeper, and it may eventually reach a depth of many
yards. In flat land, where bogs form over springs, the bog may become much
higher than the surrounding country, because of the growth of the
Sphagnum
, and
the water is held within the bog in enormous quantities. In Europe, the break–
ing out of one of these raised bogs because of excess rainfall may flood much
of the surrounding country.
The reproduction of
Sphagnum
is the principle exactly like that of the
true mosses. The sporophyte, however, is much simpler, consisting only of a
spherical spore case without a stalk. In the warm rays of the summer sunshine,
the air within the mature capsule expands and finally develops enough pressure
to blow off the lid and the entire mass of spores in one puff. If plants of
Sphagnum
with many brown, spherical capsules be brought into a warm, dry place,
the bursting open of the spore cases can be heard clearly, like the popping of
corn on a small scale.
Peat is used in many countries for fuel, and although this is not so
extensively the case in the New World, there are nevertheless in North America
millions of tons of it available in case of emergency, and it is the potential
source of hydrocarbons for many purposes. It is a standard fuel for heating
and
[:
]
cooking in many parts of northern Europe, although it does not give
off nearly as much heat as coal does, and it has a peculiar odor when burning.
When peat is compressed, it produces coal, and the idea has been proposed that
our present coal deposits came from peat bogs of extremely ancient times. This
idea is well supported by the discovery of
Sphagnum
leaves and spores in coal
EA-PS
Steere: Bryophytes
from the Rocky Mountains and from Greenland.
Hepaticae
. Hepatica is the Latin word for liver, and it was applied to
certain plants during the Middle Ages because of their liver-shaped leaves
or plant bodies. In
[:
]
medieval times, medicines came
[:
]
almost entirely
from plants, and were sometimes chosen according to a curious superstition.
It was assumed that a benevolent Creator would mark or “sign” each plant in
some way to indicate its usefulness to man. According to this pious “doctrine
of si
[:
]
gnatures,” yellow turmeric was used to treat jaundice, plants with heart–
shaped leaves were used for heart diseases, and the liver-shaped plants described
here became known as liverworts or hepatics and were widely prescribed for liver
ailments.
The name “liverwort” was applied by early botanists only to plants without
a leafy stem, and that consist of a flat, ribbon-like or somewhat liver-shaped
body of green tissue, called a thallus. However, this original concept has been
extended to include many leafy forms which had been originally placed with
mosses, so that now the true “liverwort” type makes up only about 15 per cent
of the Hepaticae, of which the remainder have leafy stems instead of a thallus.
Leafy liverworts always possess two rows of leaves and are usually con–
spicuously flattened against the soil, rotten wood, or rock upon which they
grow. Some kinds have a third row of somewhat different leaves, the underleaves.
Leafy liver
^
w
^
orts may be distinguished from mosses by the two-rowed leaves, the
lack of a midrib in the leaves, and the fact that the leaves are often variously
deeply lobed or toothed. In mosses, the leaves are arranged spirally around
the stem, usually have a midrib, and are never lobed or deeply toothed. Further–
more, the structure of liverworts is much more delicate than mosses, and they
do not withstand the rigors of drought and cold in the Arctic Zone as well as
EA-PS
Steere: Bryophytes
mosses do. Nevertheless, most liverworts are perennial and produce spore
cases each year in abundance under favorable conditions.
Liverworts reproduce in exactly the same way as do mosses, by the ferti–
lization of an egg, and the subsequent development of a diploid spore-producing
structure from the fertilized egg. The developing sporophyte of all Hepaticae
reaches its full size inside the greatly stretched archegonium that
[:
]
produced
the egg. When the spores are mature and ready for distribution, they may be re–
leased by the bursting of the spore case within the archegonium, but usually
the telescoped cells below the spore case suddenly elongate and thrust the spore
case out through the top of the archegonium and into the air on a stalk that is
sometimes several inches long.
Anthocerotes
. The
[:
]
Anthocerotes are a small group of rather rare liverworts,
sometimes called the hornworts because of the elongated cylindrical, pointed sporo–
phyte, which has the peculiar property of being able to continue growth through–
out the growing season by means of a region of dividing cells at the base. As the
sporophyte splits open at the top and mature spores escape, new cells are being
produced at a bottom. This curious manner of growth of the spore-producing
structure has led to many theories that this group might
^
be
^
in some way the “missing
link” from which higher plants developed, since all higher, or vascular, plants
as we know them are spor
^
o
^
phytes which continue growth throughout much of their
lives.
Distribution of Arctic and Subarctic Bryophytes
As has been pointed out, mosses and liverworts are able to survive extremes of
climate and local environment which most higher plants cannot tolerate. Consequently
above the timber line on mountains and north of the tree line in both hemispheres,
EA-PS
Steere: Bryophytes
the dominant plants in numbers of species, and even of individuals are often bry–
ophytes. Nevertheless, these plants are not sufficiently collected, and are too
often overlooked in ecological and floristic studies. It is not uncommon for a
detailed study of nearly any phase of arctic botany to omit a consideration of the
bryophytes altogether, even though this group is represented in every arctic region
by as many species as the higher plants. As an illustration, one may take the most
recent large publication on arctic plants. The
Botany of the Canadian Eastern Arctic
,
published by the National Museum of Canada. In this important work, a whole volume
(408 pages) is devoted to 297 species of vascular plants, whereas less than 150
pages cover 304 species of mosses and 78 spe
[:
]
^
c
^
ies of hepatics. The writer believes
that the high specialization of bryophytes to their habitat and their significance
as indicators of edaphic and environmental factors have not been properly realized
by botanists, at least in the Arctic.
During the last decade, mosses have come into general use as indicators of
forest sites and to help determine the stages of succession or stagnation in forests
and moors, especially in Scandinavia (20;91). The extension of this important
technique to North America and to the arctic regions of both hemispheres is highly
desirable.
Arctic Alaska and the Yukon
. Although no organized account of the bryophytes
of arctic Alaska and the Yukon has yet been drawn up, we have a fair idea of the
composition of that flora through several publications based on reasonably large
collections, especially the papers of Hooker and Arnott (45) on Kotzebue Sound;
Williams on the Yukon (95) and on the arctic coast of Alaska (96); and Persson
(73;74) on miscellaneous collections from the Bering Strait region and from the
Yukon. Although the coastal regions of Alaska south of and including the Aleutian
chain are extremely rich in bryophytes and have many species which are either endemic
EA-PS
Steere: Bryophytes
or of an unusual pattern of geographic distribution, arctic Alaska presents the
usual group of circumpolar species of wide distribution. A rough estimate of the
number of bryophytes of this region would be perhaps 100 species of Hepaticae and
about 300 species of Musci, including the Sphagna. In spite of
[:
]
the large number
of widespread circumpolar species, there is a surprisingly large element of species
restricted to this segment of the Arctic, some of which are endemic, others of which
are at their northern extreme in the Rocky Mountains. Examples are
Diplophyllum
imbricatum
,
Lepicolea fryei
, and
Bryobrittonia pellucida
. As a result of many col–
lections made during World War II, and of a new interest in the flora of Alaska
and the Yukon, this almost unknown region is gradually becoming better understood.
The presence of many areas which have escaped glaciations, and which, therefore, have
served as
refugia
for plants during continental glaciations, should serve as a sti–
mulus for extensive and critical study of the flora.
Canadian Western Arctic
. Perhaps the most unknown area, bryologically, of
northernmost North America is the arctic coast between the mouth of the Mackenzie
River and the Boothia Peninsula, as well as the islands of the American Arctic
Archipelago lying north of it, including especially the larger islands, as Victoria,
Banks, Melville, and Parry Islands. This region, which may be called the Canadian
Wes–
tern Arctic, has been little explored by botanists and lacks the comprehensive study
which has been given to the Canadian Eastern Arctic. Parry’s 1819-20 expedition
to Melville Island and
[:
]
Franklin’s journey to the polar sea between 1819 and 1823
both resulted in important collections of bryophytes. Except for the relatively
large collection of bryophytes made by the Canadian Arctic Expedition of 1913-18 on
the
[:
]
arctic coast and Victoria Island (96), further bryological material from the
Canadian Western Arctic is composed mostly of small collections made incidentally
EA-PS
Steere: Bryophytes
to other work. The first-known American specimens of such Siberian and Scandi–
navian species as
Radula prolifera
,
Campylium zemliae
, and
Bryum neodamense
came
from this region. Described as new from this area were
Polytrichum hyperboreum
,
Bryum calophyllum
,
B. arcticum
, and
Barbula johansenii
of which all but the last
are now known to have circumpolar ranges. Although only about a hundred Musci and
perhaps a dozen Hepaticae have been reported from the Canadian Western Arctic, it
will probably be discovered to be as rich in species as the regions east and
west of it, upon proper exploration and study.
Canadian Eastern Arctic
. The bryophyte flora of the Canadian Eastern Arctic
is relatively better known than the other arctic American floras, primarily through
the enormous collections resulting from the second expedition of the
Fram
(18).
Other large collections made more recently by Freuchen, Polunin, Dutilly, and other
have made known to a greater or lesser extent the bryophytes of nearly every major
area of the region (41;87;88). As the result of the extensive collections now
available, it has been possible to summarize rather completely
[:
]
the bryophyte
flora of the Canadian Eastern Arctic, north of 60° N. latitude (90). The total
of 304 species of Musci and 78 of Hepaticae (77) is not surpassed by the known bryo–
phyte floras of many temperate regions far to the south, many of the United States,
for example. A study of these materials demonstrates a very definite high-arctic ele–
ment in the bryophyte flora — species which flourish as far north as land exists,
to beyond latitude 82° N., yet which gradually disappear southward and are scarcely
to be found south of 60° N. latitude. Examples are
Distichium hagenii
,
Arctoa hyperbo
–
rea
,
Stegonia latifolia
,
Voitia
[:
]
hyperborea
,
Haplodeon wormskjoldii
,
Mieli
–
chhoferia macrocarpa
,
[:
]
Pohlia crudoides
,
Bryum obtusifolium
,
B. globosum
,
Cin
–
clidium subrotundum
,
C. arcticum
,
Aulacomnium acuminatum
,
A. turgidum
,
Conostomum
boreale
,
Drepanocladus berggrenii
, and
Hygrohypnum polare
. Many
[:
]
other species are
EA: PS
Steere: Bryophytes
able to exist in latitudes as northerly as the truly arctic species just listed,
but also occur in alpine habitats far to the south. These species, the arctic–
alpine species, have received considerable att
[:
]
^
en
^
tion, especially in the southern
extension of their range, since they are not rare at higher elevations in the
relatively well-studied temperate latitudes, and a list of them would be too long
to give here. Nevertheless, it is important to point out that the arctic-alpine
species are with few exceptions circumboreal in their distribution.
Greenland
. The bryophytes of Greenland are known not through any one or
more large collections as are those of Siberia and Arctic America, but through
multitudes of relatively small gatherings. Travel is difficult and distances
are great in an island that is almost two thousand miles long and
[:
]
that ex–
tends from below 60° N. latitude nearly to 84° N. latitude. Consequently, al–
though dozens of collections have been made through casual or intensive study of
small areas, no over all study of the whole island has been made in the field of
bryophytes. Unfortunately for our purposes here, there has been no comprehensive
review since 1880 of specimens and publications resulting from all the different
collections. That is something much to be desired. The volumes of
Meddelelser
om Grønland
contain many small contributions to the bryological flora of Greenland,
so that some general remarks may be made. In a very general way, one finds a
relationship between the bryophytes of southern Greenland, whose climate is tem–
pered by the Gulf Stream, and those of southern Iceland. One of the most inter–
esting indications of this affinity was the recent discovery of
Bryoxiphium norvegi
–
cum
in East Greenland. The
[:
]
greater part of the flora of East Greenland
seems to have a closer relationship with that of northern Iceland and other areas
to the east than with the American Arctic Archipelago to the west. Western
Greenland, on
[:
]
the other hand, shows in its bryophyte flora a definite agreement
EA: PS
Steere: Bryophytes
with that of Ellesmere, Devon, and Baffin Islands to the west. Approximately
150 species of Musci and perhaps 50 species of Hepaticae have been reported from
Greenland, and it is probable that further collecting by trained bryologists will
double this total from the whole island. Except for numerous species of
Bryum
(see p.000), the bryophyte flora of Greenland seems peculiarly lacking in endemic
species. Although the specific name
groenlandicum
is not unusual, nearly all the
species of bryophytes which bear it seem now to have a more or less wide circumpolar
districution. A fact of especial interest is that in Greenland bryophytes reach
their northernmost geographic extension, above 83° N. latitude, whence many species
have been reported.
Iceland
. The bryophyte flora of Iceland is now reasonably well known in its
general outlines, even though every new collection of any size seems to contain
species not previously reported. The excellent treatment of Icelandic bryo–
phytes by Hesselbo (39) and the recent report on a large collection by Meylan
[:
]
(67) give us much more material for bryogeographical considerations than is avai–
lable from most northern lands. A total of about 100 Hepaticae, more than
[:
]
20 Sphagna, and nearly 350 species of Musci have been reported. Because of its
position just south of the Arctic Circle, the sweep of the Gulf Stream along
its south coast, and the numerous hot springs, Iceland supports a surprisingly
temperate bryophyte flora, at least in certain restricted localities. Many
European species reach their northern limit of distribution here, as
Anthoceros
punctatus
,
Fossombronia dumortieri
,
Blasia pusilla
,
Archidium phascoides
,
Mnium
hornum
,
Atrichum undulatum
,
Entosthodon ericetorum
, and
Campylopus fragilis
.
One of the most interesting species in the flora of Iceland is
Bryoxiphium
norvegicum
, which in spite of its specific name is not known from Norway, but
has a curious geographical distribution in unglaciated regions of North America
EA: PS
Steere: Bryophytes
and also occurs in Mexico and the Orient (89). Endemic species seem to be few,
among which are
Bryum islandicum
,
B. groenlundii
, and
Fontin
e
^
a
^
lis islandica
.
According to Hesselbo (39), the vegetation of Iceland corresponds in its
composition most nearly with that of Scandinavia and South Greenland. All
species so far listed from Iceland, except for the
Bryoxiphium
just mentioned,
are also found in Scandinavia. Meylan (67), however, expresses the opinion that
the bryological flora of Iceland is related directly to that of north and central
Europe, since no purely American species are found there, but only American
species which are also common to Europe.
Spitsbergen
. Numerous recent collections have added some species to the
known bryological flora of Spitsbergen, but our main knowledge concerning the bry–
ophytes of these islands still depends largely on the excellent work of Berggren
(12) and Arnell (2). In view of the isolated position and high latitude of the
Spitsbergen group, the bryophyte flora is surprisingly large, with over 200
species of Musci and 50 of Hepaticae - more than have yet been found in Greenland.
Although numerous species have been described from Spitsbergen, and this name
serves as the basis for several specific epithets, most, if not all of them, have
now been found elsewhere in the Arctic. Since the bryophytes are of distinctly
arctic and arctic-alpine types,
[:
]
with a characteristic circumpolar geographic
districution, it is difficult to correlate the flora of Spitsbergen with
[:
]
that of any other polar region. However, it seems about equally close to that
of Greenland and northernmost Scandinavia.
Jan Mayen
. Jan Mayen is an isolated arctic island which is seldom visited
by botanists. According to the most recent summary of its bryophyte flora (60;61),
39 Hepaticae and 106 Musci have been collected there. This surprisingly large
EA: PS
Steere: Bryophytes
number of species indentified from so small an island may in part be due to the
fact that a bryologist has visited it. In spite of the high latitude (about 71° N.),
the flora seems not to be essentially arctic, but more related to that of Iceland
or Norway, through the large number of boreal species.
Northern Scandinavia
. Northernmost Norway, Sweden, and Finland con–
statute by far the best-known region lying so far north in the world, from a bryo–
logical viewpoint. Although its flora may not have the potential richness of the
Soviet Arctic, counting both European and Asiatic northern extensions, the bryophytes
of Scandinavia have been so thoroughly collected and studied that perhaps twice the
number of species have been found north of the Arctic Circle there than anywhere
else. Furthermore, the warm Gulf Stream which runs northward along the Norwegian
coast gives opportunity for a genuinely temperate
[:
]
flora to exist in a region that
lies latitud
^
i
^
nally quite far north, thus bringing into the area under consideration
many species which would otherwise not be able to flourish there. Through the
studies in Norway of Hagen (32) and Jørgensen (57), in Sweden by Arnell and Jensen
(9), and in Finland by Brotherus (14), as well as the
[:
]
comprehensive treat–
ments of the bryophytes of all Scandinavia by Arnell (4) and Jensen (55), the
astonishing totals of more than 500 species of mosses and perhaps 200 species of
hepatics have been reported from northern Scandinavia. The enormous collections
and the careful studies in localized areas give adequate data for careful bryo–
geographical studies, so that among the bryophytes of the Sarekgebiet of Sweden,
for example, Arnell and Jensen (9) have recognized with some confidence 6 major
floristic elements and a dozen minor ones. Furthermore, the understanding of
bryophytic associations in each habitat is so exact that it sets a model for
bryocoenological studies in other regions.
EA: PS
Steere: Bryophytes
Franz Josef Archipelago
. The group of islands which make up the Franz Josef
Archipelago have remained almost totally unknown with regard to their bryophyte
flora until relatively recently, when two important collections were made by Ivanov
in 1929 and by Savicz in 1930, during expeditions of the Soviet icebreaker
G
.
Sedov
(81;82). The 7 Hepaticae and 80 Musci now known from these islands con–
sist mostly of common arctic species of wide distribution, and seem to include no
endemic species. The affinity of this flora is difficult to determine because of
the small number of species concerned and their wide distribution. However, there
are some indications that it is most closely related to the flora of northern
Scandinavia and Siberia.
Severnaya Zemlya Archipelago
. The bryophyte flora of
[:
]
this botanically
little-known area consists of only 16 species of mosses and 1 hepatic, all of them
species of wide distribution and not uncommon on the Siberian mainland to the south
as the
[:
]
result of the 1930 expedition of
[:
]
the Russian icebreaker
G. Sedov
(82).
Soviet Arctic Mainland
. The mainland of the Soviet Arctic, taking together the
European and Asiatic segments, including Novaya Zemlya, probably has the richest
bryophyte flora, at least potentially, of any of the arctic regions. This opinion
is based on the fact that three great north-flowing rivers, the Ob, the Yenisei,
and the Lena, all serve as routes to bring species north from more temperate regions.
Furthermore, the great land mass to the south, representing very differ
^
e
^
nt floras
in widely separated regions, both in Europe and Asia, serves as an enormous reservoir
of species which in some way may find or have found their way to the Arctic. Arnell,
in 1875 and 1876, collected nearly 100 species of Hepaticae and over 400 species
of Musci in the valleys of the Ob and Yenisei rivers (64;65). In 1898,
Nilsson-Ehle collected 61 Hepaticae, 14 Sphagna, and 233 Musci in the valley of
EA: PS
Steere: Bryophytes
Lena (8). Kjellman, botanist to the
Vega
expedition along the arctic coast of
Russia and Siberia, brought back about 60 Hepaticae, 12 Sphagna, and over 150
Musci (5). These splendid collections give an excellent indication of the
richness of the bryophyte flora of arctic Russia and Siberia and are very use–
ful in charting the total distribution of arctic species. In the present state
of our knowledge concerning arctic bryophytes, it is difficult to determine if
the large num
^
b
^
er of species endemic to Siberia depends on the narrow specific
concepts of the bryologists who described them, or upon the intrinsically
richer flora. Since many of these species have now been found in arctic North
America, as
Aulacomnium acumiaatum
,
Cinclidium latifolium
,
Dicranum fragilifolium
,
Diplophyllum microdontum
, and
Radula prolifer
^
a
^
, it is probable that the latter
alternative is the correct one. There still remain many species restricted to
Siberia, as
Scapania rufidula
,
Calycularia laxa
,
Scouleria rschewini
,
Myrinia
rotundifoliu
,
Dicranum tundrae
, and
Didymodon rotundatus
.
General Considerations
A striking feature of truly arctic mosses, to be seen from the foregoing
discussions of different areas and from the tabular depiction of geographical
ranges (see Table I), is that a large number of them are circumpolar. The
relatively low degree of endemism, and the fact that many of
[:
]
those species
long considered to be endemic have now been discovered in other and widely sepa–
rated areas, leads naturally to the opinion that careful collection and study
in the future will
[:
]
greatly extend the range of almost all polar species of
bryophytes. The recent discovery in the American Arctic of Siberian species
with a very limited distribution, as
Radula prolifera
,
Dicranum fragilifolium
,
[:
]
EAPS Steere: Bryophytes
|
TABLE I. Known Distribution of some Arctic and Subarctic Bryophytes.
Key
|
|
1.
|
Arctic Alaska
|
10.
|
Jan Mayen
|
|
2.
|
Canadian Western Arctic
|
11.
|
Northern Scandinavia
|
|
3.
|
Canadian Eastern Arctic
|
12.
|
Franz Josef Land
|
|
4.
|
Ellesmere Island
|
13.
|
Severnaya Zemlya
|
|
5.
|
Baffin Island
|
14.
|
Novaya Zemlya
|
|
6.
|
West Greenland
|
15.
|
Yenisei region
|
|
7.
|
East Greenland
|
16.
|
Lena region
|
|
8.
|
Iceland
|
17.
|
Alps and Rockes
|
|
9.
|
Spitsbergen
|
|
|
|
Plant
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
11
|
12
|
13
|
14
|
15
|
16
|
17
|
|
Hepaticae
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Anthelia julaces
|
*
|
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
|
|
|
|
|
|
A. Juratzkana
|
*
|
|
*
|
*
|
*
|
*
|
|
*
|
|
*
|
*
|
*
|
|
*
|
*
|
*
|
|
|
Arnellia fennica
|
*
|
*
|
|
*
|
|
|
*
|
|
*
|
|
*
|
|
|
|
*
|
*
|
|
|
Cephaloziella verrucosa
|
|
*
|
|
*
|
|
|
*
|
|
*
|
|
|
|
|
|
|
|
|
|
C. divaricata v. incurva
|
|
|
|
|
|
|
|
|
|
|
|
*
|
|
|
|
|
|
|
Clevea hyalina
|
|
|
*
|
*
|
|
*
|
*
|
|
*
|
|
*
|
|
|
|
|
|
|
|
Gymnomitrium concinnatum
|
|
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
|
*
|
*
|
*
|
|
|
G. corallioides
|
*
|
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
*
|
*
|
|
|
Jungermannia polaris
|
|
|
|
*
|
|
|
*
|
|
|
*
|
|
|
|
|
|
*
|
|
|
Lophozia groenla
[:
]
ndica
|
|
|
|
|
|
|
*
|
|
*
|
|
|
|
|
|
|
|
|
|
L. murmanica
|
|
|
|
*
|
|
|
|
|
|
*
|
|
|
|
|
|
*
|
|
|
Marsupella groenlandica
|
|
|
*
|
*
|
*
|
|
*
|
|
|
|
|
|
|
|
|
|
|
|
Mesoptychia sahlbergii
|
*
|
|
|
*
|
|
|
|
|
|
|
|
|
|
|
*
|
*
|
|
|
Odontoschisma macounii
|
|
|
*
|
*
|
|
|
|
*
|
|
*
|
|
|
|
|
*
|
*
|
|
|
Peltolepis grandis
|
|
|
|
|
|
|
*
|
|
|
|
*
|
|
|
|
*
|
|
|
|
Plagiochila arctica
|
*
|
*
|
*
|
*
|
|
|
|
|
|
|
|
|
|
|
|
*
|
|
|
Pleuroclada albescens
|
*
|
|
|
*
|
*
|
*
|
*
|
*
|
|
*
|
*
|
|
|
|
*
|
|
|
|
Prasanthus suecicus
|
|
|
|
|
|
|
*
|
|
|
*
|
*
|
|
|
|
*
|
|
*
|
|
Radula prolifera
|
*
|
*
|
|
|
|
|
|
|
|
|
|
|
|
|
*
|
*
|
|
|
Sauteria alpina
|
|
|
*
|
|
|
*
|
*
|
*
|
|
*
|
*
|
|
|
|
*
|
*
|
|
|
Scapania simmonsii
|
|
|
|
*
|
|
|
|
|
|
|
|
|
|
|
*
|
*
|
|
|
S. spitsbergensis
|
|
|
|
|
|
*
|
*
|
|
*
|
|
*
|
|
|
|
*
|
*
|
|
|
Temnoma setiforme
|
*
|
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
|
|
*
|
*
|
*
|
|
|
Musci
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Andread blyttii
|
*
|
|
|
|
*
|
*
|
*
|
|
*
|
|
*
|
|
|
|
|
|
|
|
A. obovata
|
*
|
|
*
|
|
|
*
|
|
*
|
|
*
|
|
|
|
|
*
|
|
|
|
A. papillosa
|
|
|
*
|
*
|
|
|
*
|
|
*
|
|
*
|
*
|
|
*
|
*
|
*
|
|
|
Aongstroemia longipes
|
*
|
|
|
|
|
*
|
|
*
|
*
|
|
*
|
|
|
|
|
|
*
|
EA: PS
Steere: Bryophytes
|
Table I continued
|
|
Plant
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
11
|
12
|
13
|
14
|
15
|
16
|
17
|
|
Aulacomnium acuminatum
|
*
|
*
|
*
|
*
|
*
|
|
|
|
|
|
|
|
|
|
*
|
*
|
|
|
A. turgidum
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
*
|
*
|
|
|
Brachythecium turgidum
|
|
|
|
|
|
|
|
|
*
|
*
|
*
|
|
|
|
*
|
*
|
|
|
Bryum archangelicum
|
|
|
|
|
|
*
|
*
|
|
*
|
*
|
*
|
|
|
|
*
|
|
|
|
B. arcticum
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
*
|
*
|
|
|
B. globosum
|
|
*
|
*
|
*
|
|
*
|
|
|
*
|
|
*
|
|
|
|
*
|
*
|
|
|
B. obtusifolium
|
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
|
*
|
*
|
|
*
|
*
|
*
|
|
|
B. rutilans
|
|
*
|
*
|
*
|
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
*
|
|
|
|
Calliergon turgescens
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
*
|
*
|
|
|
Campylium zemliae
|
*
|
|
|
|
|
*
|
|
|
|
|
|
*
|
*
|
*
|
|
|
|
|
Cinclidium arcticum
|
|
*
|
*
|
*
|
*
|
|
|
|
*
|
|
*
|
|
|
*
|
*
|
*
|
|
|
C. latifolium
|
|
|
*
|
|
|
|
|
|
|
|
|
|
|
|
*
|
*
|
|
|
C.
[:
]
polare
|
|
|
*
|
*
|
|
|
|
|
|
|
|
|
|
|
*
|
*
|
|
|
C. subrotundum
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
|
|
*
|
|
|
*
|
*
|
*
|
|
|
Conostomum boreale
|
*
|
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
|
*
|
*
|
*
|
*
|
|
Cratoneuron curvicaule
|
|
|
|
|
|
|
|
*
|
*
|
|
*
|
*
|
*
|
|
*
|
*
|
*
|
|
Desmatodon suberectus
|
|
|
*
|
*
|
|
|
*
|
|
|
|
*
|
*
|
*
|
*
|
*
|
*
|
|
|
Dicranum angustum
|
|
|
|
|
|
|
*
|
*
|
*
|
|
*
|
|
|
|
*
|
*
|
|
|
D. arcticum
|
|
|
|
|
|
*
|
|
*
|
|
|
|
|
|
|
|
|
|
|
D. elongatum
|
*
|
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
*
|
*
|
|
|
D. fragilifolium
|
*
|
|
|
|
|
|
|
|
|
|
*
|
|
|
|
*
|
*
|
|
|
D. hyperboreum
|
|
|
|
|
*
|
|
|
|
|
|
|
|
|
|
|
|
|
|
D. neglectum
|
*
|
*
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Didymodon rufus
|
|
*
|
*
|
*
|
|
*
|
|
*
|
|
|
*
|
|
|
*
|
|
*
|
|
|
Distichium hagenii
|
|
*
|
*
|
*
|
|
|
*
|
|
|
|
*
|
|
|
*
|
*
|
*
|
|
|
D. inclinatum
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
|
|
|
*
|
*
|
|
|
Ditrichum flexicaule
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
D. giganteum
|
*
|
*
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Drepanocladus badius
|
*
|
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
|
*
|
*
|
*
|
|
|
D. berggrenii
|
|
|
|
*
|
|
*
|
*
|
|
|
|
*
|
|
|
|
|
|
|
|
D brevifolius
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
|
|
|
|
*
|
|
|
|
|
D. latifolius
|
|
*
|
*
|
*
|
|
|
|
|
*
|
|
|
*
|
*
|
*
|
*
|
*
|
|
|
D. tundra
|
|
|
|
|
|
|
|
|
|
|
|
*
|
|
|
*
|
|
|
|
Fissidens arcticus
|
|
|
|
*
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Funaria Polaris
|
|
|
*
|
*
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Haplodon wormskjoldii
|
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
|
*
|
*
|
|
*
|
*
|
*
|
|
|
Hygrohypnum polare
|
*
|
|
|
*
|
|
*
|
*
|
|
*
|
|
*
|
*
|
*
|
*
|
*
|
*
|
|
|
Hypnum revolutum
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
*
|
*
|
*
|
|
Mielichhoferia macrocarpa
|
|
|
*
|
*
|
|
*
|
|
|
|
|
|
|
|
|
|
|
*
|
|
Myurella tenerrima
|
|
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
*
|
*
|
|
|
Oligotrichum incurvum
|
*
|
|
|
|
*
|
*
|
*
|
*
|
|
|
*
|
|
|
|
|
|
|
|
Oncophorus schisti
|
*
|
|
|
*
|
*
|
|
*
|
|
|
|
*
|
|
|
|
*
|
|
|
|
Orthothecium acuminatum
|
|
|
|
*
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
O. chryseum
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
Orthothecium strictum
|
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
*
|
*
|
*
|
*
|
|
*
|
*
|
*
|
|
Orthotrichu
[:
]
m killiasii
|
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
|
|
|
|
*
|
|
|
Philonotis tomentella
|
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
*
|
*
|
|
*
|
*
|
*
|
|
EA: PS
Steere: Bryophytes
|
Table I continued
|
|
Plant
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
11
|
12
|
13
|
14
|
15
|
16
|
17
|
|
Polytrichum fragile
|
|
|
|
*
|
|
|
*
|
|
*
|
|
|
*
|
|
|
|
|
|
|
P. hyperboreum
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
*
|
*
|
|
|
|
*
|
*
|
|
|
P. jensenii
|
*
|
|
*
|
|
*
|
*
|
*
|
|
*
|
|
*
|
*
|
|
|
*
|
|
|
|
Pottia heimii, v. obtusifolia
|
|
*
|
*
|
*
|
|
*
|
*
|
*
|
*
|
|
*
|
*
|
|
|
*
|
*
|
|
|
Psilopilum cavifolium
|
*
|
|
*
|
|
|
|
|
*
|
*
|
|
*
|
*
|
|
*
|
|
|
|
|
P. laevigatum
|
|
|
|
*
|
*
|
*
|
|
*
|
*
|
|
|
|
|
|
*
|
*
|
|
|
Rhacomitrium lanuginosum
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
*
|
*
|
*
|
|
Scouleria rschewini
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
*
|
*
|
|
|
Seligeria Polaris
|
|
|
|
|
|
|
|
|
*
|
|
|
|
|
|
|
|
|
|
Spalachnum vasculosum
|
|
*
|
*
|
*
|
|
*
|
*
|
*
|
*
|
|
*
|
*
|
|
*
|
*
|
*
|
|
|
Stegonia latifolia
|
|
|
|
*
|
*
|
*
|
*
|
*
|
*
|
|
*
|
*
|
|
*
|
*
|
*
|
|
|
Tetraplodon bryoides
|
|
|
*
|
*
|
*
|
*
|
*
|
|
|
|
|
*
|
|
*
|
*
|
*
|
|
|
Timmia norvegica
|
*
|
*
|
*
|
*
|
|
|
*
|
|
|
*
|
*
|
|
|
*
|
*
|
*
|
|
|
Voitia hyperborea
|
|
*
|
*
|
*
|
*
|
|
|
*
|
|
|
|
|
|
*
|
*
|
|
|
EA: PS
Steere: Bryophytes
Cinclidium latifolium,
and
Aulacomnium acuminatum
, and the reciprocal discovery
in Siberia of several species previously considered endemic to the American Arctic,
as
Scapania simmonsii
and
Plagiochila arctica
, well illustrates this point. The
generalized circumpolar geographical distribution of the arctic bryophytes seems
to indicate that their invasion of the Arctic Zone was very ancient indeed, since
their migration under present conditions must be exceedingly slow.
The stability of specific types is also a remarkable feature of arctic
bryophytes. Although all of them show the usual response in growth to unfavora–
ble environmental conditions, under the same conditions specimens form widely
separated localities appear almost identical. The only govern which seem highly
variable genetically are
Drepanocladus
and
Calliergon
among the Pleurocarpae,
and
Bryum
in the Acrocarpae. Since
Drepanocladus
and
Calliergon
are represented
by relatively few species, the problem is not particularly acute.
Bryum
, how–
ever, has proliferated in the Arctic zone in much the same manner as
Taraxacum
,
and perhaps through the same methods. Although apomictic clones are not known
yet in mosses, apospory is not uncommon in them. A thorough study of the more
than 100 species of
Bryum
in the Arctic with modern genetical and cytological
techniques would produce results of the greatest scientific interest, and might
clarify some of our present problems concerning specific concepts in Musci.
Bryophyte Associations in the Arctic
. As bryophytes are extremely sensi
v
^
t
^
ive
to edaphic and climatic factors, one finds a surprisingly large series of differ–
ent associations, reflecting sometimes only very small differences in habitat
conditions. The absence of trees in all arctic regions removes the complicated
series of forest associations, and so the factors which influence the distribu–
tion and association of bryophytes are primarily the nature of the substratum, the
amount of water through all or part of the year, the amount of insolation, ex–
posure to wind, and temperature. In any given habitat, the amount of water seems
EA: PS
Steere: Bryophytes
to be the most important limiting factor in determining which species may exist
there.
With the exception of members of the Splachnaceae, which usually grow on
dung, bones, and other animal materials, the usual substrata for arctic bryo–
phytes are soil and rock. Alkalinity in terms of calcium ion, and acidity in
terms of hydrogen ion are factors which affect the distribution of species most
conspicuously. In alkaline to neutral marches and bogs, on e finds a very
different flora from that occurring in acid ones, with a strong development
of such conspicuous species as
Drepanocladus revolvens, Scorpidium acorpioides,
Paludella squarrosa
,
Calliergon sarmentosum
,
C. turgescens
,
C. trifarium
,
Cinclidium stygium
,
Meesea triquetrs
, and
Philonotis tomentella
. In acid
[:
]
bogs and swamps, Sphagnum species are not only the most predominant plants, but
also the most actice acidifying agents. However, the greatest development of
acid bogs and muskegs is in the subarctic zone, since
Sphagnum
is not primarily
an arctic genus, and it gradually disappears northward, not only in number of
species, but also in number of individuals.
Sphagnum
species are usually ac–
companied in the Arctic Zone by (and may be replaced by) species of
Dicranum,
Polytrichum
[:
]
strictum
,
Aulacomnium palustre
,
Pohlia nutans
,
Calliergon
stramineum
,
Tomenthypnum nitens
, and many Hepaticae.
On soil, under mesophytic conditions, the bryophyte associations are very
rich in species, especially in such genera as
Polytrichum
,
Pogonatum
,
Timmia
,
Hylocomium
,
Lophozia
,
Cephalozia
, and many others. In this habitat, the genus
Bryum
finds its maximum expression, and has developed specialized species which
seem to fill even the
[:
]
most minute cological niches throughout the mesophytic
formation. On more calcareous and somewhat
[:
]
drier soil, one finds species of
[:
]
Tortula, Distichium, Ditrichum, Encalypta, Myurella, Orthothecium
,
EA: PS
Steere: Bryophytes
Peltolepis, Sauteria
, etc. In xerophytic habitats, especially on acid soil
and rock,
Rhacomitrium lanuginosum
finds its greatest development, and may form
a ground cover or heath several inches thick and, in some places, several
miles in extent. Where conditions are too dry for
Rhacomitrium
to flourish,
scattered tufts of
Grimmia
and
Andreaea
may be the only vegetation of any kind.
In neutral of alkaline areas, species of
Dicranum
mixed with other bryophytes
may produce thick cushions or mats on rock and soil, and form the dominant vege–
tation over large areas.
One of the most characteristic features of arctic mosses and liverworts is the
great mixture in which they grow. It is not uncommon to find twenty species in
a clump the size of one’s hand, and this fact is emphasized by nearly all bryo–
logists who have studied arctic material. Each microhabitat seems to develop
its own little flora which grades into the next microhabitat, which may be only
a few inches away and yet have its own group of species.
Problems in Arctic
[:
]
Bryology
. This discussion would not be complete with–
out a brief statement of some of the problems open to a bryologist in the Arctic,
beyond the simple fact that a large number of species not previously reported can
be added to our lists. Careful collecting by trained bryologists and their exten–
sive field notes will solve many problems of phytogeographical distribution. The
abundance of any particular species can be judged only by a bryologist in the
field; inferences drawn from herbarium material alone can hardly be trusted,
since the average collector will soon shun the common species and yet pick up
the rare species every time he meets them. Relative abundance of any species may
show its ecological preferences with relation to altitude and habitat, and may
even give information on paths of migration.
EA: PS
Steere: Bryophytes
One of the most interesting phytogeographic problems is the determination
of local distribution of rare or relict species, many of which show disjunction of
geographic range to a greater or lesser degree. The effect of the rigorous
arctic climate on the different species and floristic elements has never been
studied as an ecological problem, but only with reference to taxonomy. Why is it
that some species are extremely reduced and barely surviving, whereas others are
robust and flourishing? Life forms and growth forms of arctic bryophytes need study
as does even the time of fertilization and maturation of sporophyte. The physio–
logical reasons for the lack of spore production by many arctic bryophytes need
study, as well as their adjustment to the long, dark winter months. The success–
sion of species of bryophytes in different
[:
]
habitats in Arctic is completely
unknown. The study of natural moss communities has been reasonably well studied
in north
^
e
^
rn Scandinavia but throughout most of the polar regions this important
field of bryocoenology remains almost completely unstudied.
To summarize, although in arctic regions the bryophytes have often been
collected casually and incidentally to flowering plants, there may actually be
more species of bryophytes about which we know very little, and whose study in a
detailed manner by bryologists in the field may
[:
]
well halp solve
[:
]
some of the
many problems of arctic botany.
William Campbell Steere
EA: PS
Steere: Bryophytes
BIBLIOGRAPHY
1. Andrews, A.L. “Additions to the bryophyte flora of Iceland,”
Bryologist,
vol.26, p.4, 1923.
2. Arnell, H.W. “Beiträ
a
ge zur Moosflora der Spitzbergizchen Inselgruppe,”
Finska Vetenskops-Soc.
Oversigt Főrh
.vol.57, pp. 99-130,
1900.
3. ----.
Lebermoosstudien im Nőrdlichen Norwegen
. Jőnkőping, 1892.
4. ----. “Levermossor,” Holmberg, or.
Skandinaviens Flora
, Stockholm, 1928.
5. ----. “Die Moose der Vega-expedition,” Arkiv főr Bot. vol.15, no.5. pp.
1-111, 1917.
6. ----. “Die Moosvegetation an den von der Schwedischen Jenissei-expedition
im jahre 1876 besuchten Stellen,”
Annales Bryol
. Vol.1,
pp. 1-9, 1928.
7. ----. “Die Moosvegetation an den von der Schwedischen Jenissei-expedition
im jahre 1876 besuchten stellen. II,” Ann. Bryol. Vol.3,
pp. 1-24, 1930.
8. ----. “Zur Moosflora des Lena-Tales, Bericht űber die im
[:
]
jahre 1898
von Herrn Doctor H. Nilsson-Ehle an der Lens gesammelten
Moose,”
Arkiv főr Bot
. vol.13, no.2, pp. 1-94, 1913.
9. ---- & Jensen, C. “Die Moose des Sarekgebietes,”
Naturwissenschaftliche
Untersuch. Sarekgeb. Schwed.-Lapp
. Vol.3. pp.71-132, 1907;
vol.3. pp. 133-268, 1910.
10. Bachurina, A. “On the bryolflora of the Yenissey river basin (Krasnoyarsk
Region),” Akad. Nauk Kiev Inst. Bot.
Zhurnal
, vol.23, no.
31, pp. 81-116, 1939. (English summary.)
11. Bell, Robert. “List of plants collected by Dr. R. Bell around the shores of
Hudson’s Bay and along the Churchill and Nelson Rivers in
1877 and 1879,” his
Report on Explorations on the
[:
]
Churchill
and Nelson Rivers
[:
]
and around God’s and Island Lakes
,
1879. Montreal, Dawson, 1880. Appendix 2.
EA: PS
Steere: Bryophytes
12. Berggren, S. “Musci et Hepaticae Spetsbergenses. Bericht űber die Unter–
suchung der Moosflora Spitzbergens und Beeren-Eilands währ–
end der schwedischen Expedition 1864 and 1868, and Verzeich–
nis der dort gesammelten Arten,” Svenska Vetenskapsakad.
Handl
. Vol. 13, no. 7, pp. 1-103, 1875.
13. Blytt, A. “Bidrag til Kundskaben om Vegetationen paa Nowaja Semlja,
Waigatschően og ved Jugorstraedet. (Efter Samlinger
hjembragte fra den Rosenthelske Expedition i 1871 ved
Hr. Student Aagaard),” Norske Videnskaps-Akad.,
Forh.,
1872. pp. 13-23.
14. Brotherus, V.F. “Die Laubmoose Fennoskandias,” Flora Fennica, vol. 1,
pp.
[:
]
1-635, 1923.
15. ----. “Die Moose des arctischen Kűstengebietes von Sibirien, nach der Sam–
mlung der Russischen Nordpolar-Expedition 1900-1903,” Akad.
Nauk. Classe Phys.-Mat.
Mem. Zapiski
, ser.8, vol.27, no.2,
pp. 1-15, 1910.
16. Brown, Robert. “A list of plants, collected in Melville Island, by the
officers of the expedition; with characters and descriptions
of the new species,” Parry, W.E.
Journal of a voyage for the
Discovery of a North-West passage in the years 1819-20.
London, Murray, 1821. App. no. XI.
17. Bryhn, Nils. “Ad cognitionem Bryophytorum arcticorum contributions sparsae,”
Norske Videnskaps.-Akad.
Forh.
no.5, pp. 1-27, 1908.
18. -----.
Bryophyta in Itinere Polari Norvagorum Secundo Collecta (Fortegnelse
over de under den 2den Norske Polarexpedition Indsamlede Moser
).
Kristiania, Brøgger, 1906.
Report of the Second Norwegian
Arctic Expedition in the “
[:
]
Fram
.” 1898-1902. no. 11.
19. -----. “Bryophyta pro flora Spitzbergensi nova,”
Nytt Magazin. Naturv
.
vol.47, no. 11 pp. 207-08, 1909.
20. Cajander, A.K. “The theory of forest types,”
Acta For. Fenn.
Vol.31, pp.
1-108, 1926.
21. Cardot, J. & Th
e
^
é
^
riot, I. “The mosses of Alaska,” Wash. Acad. Sci.
Proc
.
vol.4,pp. 293-372, 1902.
Pl.
[:
]
13-23
.
22. Dixon, H.N. “The mosses of the Oxford University expedition to Spitz–
bergen, 1921,”
Bryologist
, vol. 25, pp. 86-89, 1922.
EA: PS
Steere: Bryophytes
23. ----. “Notes on the mosses of the Oxford University expedition to West
Greenland, 1928,”
Bryologist
, vol. 32, pp. 1-3, 1929.
24. ----. “Spitzbergen mosses,”
Bryologist
, vol. 25, pp. 86-89, 1922.
25.
[:
]
Ekstam, Otto. “Beiträge zur Kenntnis der Musci Novaja Semlja’s,”
Tromsø Mus. Aarsh
. Vol. 20, pp.72-80, 1898.
26. Evans, A.W. “Notes on the Hepaticae collected in Alaska,” Wash. Acad.
Sci.
Proc
. vol. 2, pp. 287-314, 1900.
27. -----. Report on the Hepaticae of Alaska. Torrey Bot. Club
Bull.
vol.
41, pp. 577-616, 1914.
28. -----. “Yukon Hepaticae,” Ottawa Naturalist, vol. 17, pp.13-14, 1903.
29. Frye, T.C. and Clark, Lois. “Hepaticae of North America,” Wash. Univ.
Publ. Biol
. Vol.6, pp.1-733, 1937-46, (still incomplete).
30. Geheeb, A. “Beitrag zur Moosflora des westlichen Sibiriens,”
Flora
, Jena,
vol. 62, pp. 471-80, 1879.
31. Grout, A.J.
Moss Flora of North America, North of Mexico
. Newfane, Vt.,
1928-40. 3 vols.
32. Hagen, I. “Forarbejder til en norsk løvmosflora. I-XXXI,” Norske Videnskaps–
Akad.
Skrifter
. 1908-1929.
33. -----, and Porsild, M.P. “Descri
t
ptions de quelques esp
e
^
è
^
ces novelles de
Bryac
e
^
é
^
es r
e
^
é
^
colt
e
^
é
^
es sur l’Ile de Disko”
Medd. Grønland
, vol.
36, pp. 435-65, 1904.
Pl.X-XV.
34. Haring, Inez M. “Mosses collected by the Robert A. Bartlett Greenland
Expedition 1940,”
Bryologist
, vol.46, pp.88-91, 1943.
35. Harmsen, L. “Mosses,”
Medd. Grønland
,” vol. 104,no. 7,pp. 1-40,
[:
]
1933.
36. -----, and Seidenfaden, G. “The Godthaab expedition 1928. The Mosses,”
Medd. Grønland
, vol.30, pp. 313-32, 1907.
37. Herzog, Theodor.
Geographie der Moose
. Jena, Fischer, 1926.
38. Hesselbo, August. “Bryophyta,” Gandrup, “A botanical trip to Jan Mayen,”
Dansk Bot. Arkiv
, vol.
[:
]
4, no. 5, pp. 28-34, 1924.
39. ----. “The Bryophyta of Iceland,” Rosenvinge, L.K. and Warming, Eugene,
The Botany of Iceland,
I, 2, pp.395-675, 1918.
40. ----. “List of the Andreaeales and Bryales found in East-Greenland between
74° 15′ and 65° 35′ lat. N. in the years 1898-1902,”
Medd
.
Grønland, vol.30, pp. 313-32, 1907.
EA: PS
Steere: Bryophytes
41. ----. “Mosses collected on the Fifth Thule Expedition determined by A.
Hesselbo,” Thule Expedition, 5th
[:
]
1921-24.
Report
vol.2,
no.2.Gyldendalske Boghandel, Nordisk Forlag, Copenhagen, 1937.
42. ----. “Mosses collected on the north-coast of Greenland by the late Dr.
Th. Wulff,”
Medd. Grønland
, vol. 64, pp. 269-77, 1923.
43. ----. “Mosses from North-East Greenland (N. of 76° N. Lat.) collected by
the “Danma
k
rk-Expedition” 1906-08,”
Medd. Grønland
, vol.43,
pp. 169-80.
Pl. XI, XII, 13 figs
.
44. ----. “Some mosses from N. W. Greenland (Wolstenholme Sound and Inglefield
Gulf),”
Medd. Grønland
, vol. 64, pp. 215-20, 1923.
45. Hooker, W.J. and Arnott, G.A.W.
The Botany of Captain Beechey’s Voyage
;
Comprising an Account of the Plants Collected by Messrs. Lay and
Collie, and Other Officers of the Expedition, During the voyage
to the Pacific and Behring’s Strait, Performed in His Majesty’s
Ship Blossom, under the Command of Captain F.W. Beechey, in the
Years 1825, 26, 27, and 28
. London, Bohn, 1841
[:
]
46. Howe, M.A. “Contributions to the botany of the Yukon Territory. 1. en enumera–
tion of the
[:
]
Hepaticae collected by R.S. Williams, 1898-1899,”
N.Y. Bot
[:
]
Gdn.
Bull
.vol. 2, pp. 101-105, 1901.
Pl.14
.
47
.
Hultén, Eric.
Outline of the History of Arctic and Boreal Biota during the
Quarternary Period: Their Evolution during and after the Glacial
Period as
[:
]
Indicated by the Equiformal Progressive Areas
of Present Plant
[:
]
Species
. Stockholm, Aktiebolaget Thule, 1937.
48. Jansen, Christian. “Bryophyta,”
Botany of the Faerőes
. Copenhagen, Nordiske
forlag, 1901, vol.1, pp. 120-97,
pl.2-6
.
49. ----. “Enumeratio Hepaticarum insulae Jan Mayen et Broenlandiae orientalis
a cl. P. Dusen in itinere groenlandico Suecorum anno 1899
collectarum,” Svenska Vetenskapsakad.
Őfvers. Főrn
., no.6,
pp. 795-802, 1900.
50. ----. “Hepaticae and Sphagnaceae from North-East Greenland (n. of 76° N. lat.)
collected by the ‘Denmark-Expedition’ 1906-08,”
Medd. Grønland
vol. 43; pp. 163-67, 1910.
51. ----. “List of the Hepaticae and Sphagnales found in East-Greenland between
75° and 65° 35′ lat. N. in the years 1898-1902,”
Medd. Grønland
,
vol.30, pp. 295-312, 1906.
52. ----. “Mosser fra Novaia-Zemlia, semlede paa Dijmphna-expeditionen 1882-83
af Th. Holm,” Dijmphna-Togtets zool.-Bot. Udbytte. Musci,
pp. 61-70, 1887.
EA: PS
Steere: Bryophytes
53: -----. “Mosser fra Øst-Grønland,”
Medd. Grønland
, vol. 15, pp. 363-445,1898.
54. -----. “Musci Asiae Borealis. Beschreibung der von den schwedischen Expedi–
tionen nach Sibirien in den Jahren 1875 und 1876 gesammelten
Moose, mit Berűcksichtingung aller frűheren bryologischen
Angaben fűr das russische Nord-Asien. 3. Teil: Torfmoose,
Svenska Vetenskapsakad.
Handl.
vol.44, no. 5, pp. 1-18, 1909.
55. -----.
Skandinaviens Bladmossflora
. København, Munksgaard, 1939.
56. Jones, E.W. “Notes on the bryophyte flora of Gr
i
^
í
^
msey and other parts of
North Iceland,”
Bryologist
, vol. 49, pp. 14-29, 1946.
57. Jørgensen, E. “Norges Levermoser,” Bergens Mus.
[:
]
Skrifter
, vol. 16, pp.
1-343, 1934.
58. Lange, J. & Jensen, C. “Grønlands Mosser. Bryptogamae cellulares:
[:
]
Muscineae,”
Medd. Grønland
, vol.3, pp. 309
p
^
-
^
443, 1887.
59. Lee, L.W. “Some bryophytes of Greenland,”
Bryologist
, vol. 47, pp. 114-18,1944.
60. Lid, J. “
[:
]
Bryophytes of Jan Mayen,” Norsk Polarinstitutt,
Medd
. vol.48,p.1-13,
1941.
61. ----. “Bryophytes of Jan Mayen,”
Trav
[:
]
. Bryol
. vol. 1 pp. 54-62, 1942.
62. ----.
Sphagna from Novaya Zemlya with an Appendix by E. Jørgensen: Some
mosses from Novaya Zemlya
. Oslo, Brøggers, 1924. Norwegian
Expedition to Novaya Zemlya, 1921.
Report of the Scientitic
Results
. No. 20.
63. Lindberg, S. O. “Főrteckning őfver mossor, insamlade under de svenska ex–
peditionerna till Spitsbergen
[:
]
1858 och 1861,” Svenska
Vetenskapsakad. Ő
fvers. F
ő
rh
. vol. 23, pp. 535-61, 1867.
64. ----, and Arnell, H.W. “Musci Asiae Borealis. Beschreibung der von den
schwedischen Expeditionen nach Sibirien in den Jahren 1875 und 1876
gesammelten Moose mit Berűcksichtigung aller frűheren bryologi–
[:
]
schen Angaben fűr das russische Nord-Asien. I. Levermoose,”
Svenska Vetenskapsakad.
Handl
. vol. 23, no. 5, pp. 1-69, 1889.
65. ----, ------. “Musci Asiae Borealis. II. Laubmoose,” Svenska Vetenskapsakad.
Handl
. vol. 23, no. 5, pp. 1-
[:
]
163 1890.
66. Mathey-Dupraz, A. “Notes sur la flore du Spitzberg,” Soc. Neûchâtel. Sci.
Nat.
Bull
. vol. 39, pp. 49-63, 1912.
67. Meyland, C. “Contribution à la
[:
]
connaissance de la flore byologique
de l’Islande,” Schweizerische Bot. Gesell.
Bericht
, vol. 50,
pp. 475-99, 1940.
EA: PS
Steere: Bryophytes
68. Mitten, W. “Mosses and Jungermanniae,” Nares, G.S.,
Narrative
[:
]
of a Voyage
to the Polar Sea during 1875-6 in H.M. Ships “Alert’ and ‘Dis
–
covery
.’ London. Low, Marston, Searle, Rivington, 1878, vol.2,
pp. 313-19.
69. Mőller, H. “Lővmossornas utbredning is Sverige, I-XIII,”
Arkiv főr Bot.
vols. 10-
[:
]
28, 1911-36.
70. Műller, C. “Musci Tschuctschici,”
Bot. Centralbl
. vol. 16, pp. 57-63, 91-95,
121-27, 1883.
71. Ostenfeld-Hansen, C. “Contribution a la flore de l’ile Jan-Mayen,” B
otanisk
Tidsskr
. vol.1, pp. 18-32, 1897.
72. Persson, H. “Arctic bryophytes mainly collected by the Rev. J. Lagerkranz,”
Svensk Bot. Tidskr
. Vol.36, no.4, pp. 444-50, 1942.
73. ----. “Further notes on Alaskan-Yukon bryophytes,”
Bryologist
, vol. 49,
pp. 41-58, 1946.
74. ----. “Some Alaskan and Yukon bryophytes,”
Bryologist
, vol.49, pp. 41-58,
1946.
75. ----. “Till kännedomen om Lofotens mossflora,”
Nytt Magazin Naturv
. vol.80,
pp. 113-35, 1939.
76. Polunin, Nicholas.
Botany of the Canadian Eastern Arctic, Part I. Pteridophyta
and Spermatophyta
. Ottawa, Patenaude, 1940. Nat. Mus. Can.
Bull.
no. 92, Biological Ser. no.24.
77. ----. “Hepaticae,” Polunin, Nicholas, comp. & ed. Botany of the
[:
]
Canadian
Eastern Arctic, Part II.
Thailophyta and Bryophyta
. Ottawa, 1947,
pp. 491-512.
78. Richardson, John. “Botanical appendix,” Franklin John.
Narrative of a Journey
to the Shores of the Polar Sea, in the Years 1819, 20, 21,and 22.
London, Murray, 1823, pp. 729-68.
79. Savich, L.I. “Enumeration des mousses du Gouvernement Archangel,” Leningrad
Glavnii Bot. Sad.
Izv
. Vol.20, pp. 25-33, 1921.
80. ----. “Kronika. Eriologicheskaya Poezdka na Novuyu Zemlyu letom 1935 Goda.”
Sovetskaia Bot.
1936, no. 4, pp. 135-41.
81. ------. “Mkhi Zemli Frantsa-Iosifa, Sobrannye I.M. Ivanovym vo Vremia Poliarnoi
Ekspedits
s
ii 1929 Goda na Ledokolnom Parokhode ‘G. Sedov.’”
(Mosses of Franz Josef Land collected by J.M. Ivanov at the time
of the 1929 exped. of the ‘Sedov.’) Leningrad, VSesoiuznyi Ark.
Inst.
Trudy
, vol. 2, pp. 63-79, 1932. (Russian with resume in
French.)
EA: PS
Steere: Bryophytes
82. ----. “Les mousses de l’Archipel Fran
c
^
ç
^
ois-Joseph, Severnaia Zemlia,
I
^
Î
^
le
Wiese, r
e
^
é
^
c
o
^
ò
^
lt
e
^
é
^
es par V. P. Savicz durant l’exp
e
^
é
^
dition polarie
de 1930 sur le brise-glace G. S
e
^
é
^
dov,” Akad. Nauk. Bot. Inst.
Acta.
ser.2, vol.3, pp. 505-78, 1936.
83. ---. “Les mousses des c
o
^
ô
^
tes polaires de la Sib
e
^
é
^
rie recueillis par M.I.I.
Trshemesky,” Leningrad. Glavnii Bot. Sad.
Izv
. vol.34, pp.136-38,
1916.
84. ----. “Sphagna im Jahre 1929-1930 im Fluss
b
^
g
^
ebiet Anadyrs und Penzha-Bai
von V. B. Soczawa gesammelt,” Akad. Nauk. Dalnevost. Filial,
Vladivos.
Vestnik
vol. 16, pp. 101-07, 1936.
85. ----. “Ueber die neuen Fundorte der Mooses in arktischen Sibirien,” Leningrad.
Glavnii Bot. Sad. Inst. Sporovykh Rastenii.
Bot. Mat
. vol.3, pp.
191-92, 1924.
86. Steere, W.C. “Bryophyta of Arctic America. I. Species from Little Diomede
Island, Bering Strait, Alaska,” Amer. Midl. Nat. vol. 19,
pp. 436-39, 1938.
87. ----. “Bryophyta of Arctic America. II. Species collected by J. Dewey Sope
^
r
^
,
principally in southern Baffin Island,”
Amer. Midl. Nat
. vol.
21, pp. 355-67. 1939.
88. ----. “Bryophyta of Canadian Arctic; collection of Father Arth
e
^
è
^
m
^
e
^
Dutilly,
o.m.i.,”
[:
]
Flora Arctica; Habitat of the Eskimo.
Village Richelieu,
P.Q., Scolasticat Notre-Dame, 1941.
89. ----. “Bryoxiphium norvegicum, the sword moss, as a preglacial and interglacial
relic,”
Ecology
vol.18, pp. 346-58, 1937.
90. ----. “Musci,” Polunin, Nicholas,
Botany of the Canadian Eastern Arctic.
Part
II. Thallophyta and Bryophyta. Ottawa, 1947. Nat. Mus. Can.
Bull
. no. 97.
Biological Series,
no. 26.
91. Størmer, P.
Moser fra Skog og Myr
. Oslo, Johan Grundt Tanum, 1946.
92. Th
e
^
é
^
riot, I. “Mousses de Spitzberg,”
Revue Bryol
. vol.34, pp.36-37, 1907.
93. Thrpe, Frances J. “Bryophytes from Greenland,” Mich. Acad. Sci.
Pap
. vol.19,
pp. 281-91, 1933.
94. Warnstorf, C. “Zur Bryo-Geographie des Russischen Reiches. Eine Erinnerung
an Dr. E. Zickendrath,”
Hedwigia
vol.53, pp. 184-320; vol.54,
pp.22-182, 1913.
EA: PS
Steere: Bryophytes
95. Williams, R.S. “Contributions to the Botany of the Yukon Territory. 2.
An enumeration of the mosses collected. N.Y. Bot. Gdn.
Bull
.
vol. 2, pp. 105-48, 1901,
Pl. 15-24
.
96. ----. “Mosses,” Canadian Arctic Expedition 1913-18.
Report
. Vol. IV, Pt. E.
Ottawa,
N
^
M
^
ulvey, 1921.
97. ----. “Some farthest north lichens and mosses of the Peary Arctic Expedition
to Grant Land in 1906,”
Torreya
vol.18, pp. 210-11, 1918.
98. Wynne, Frances E. and Steere, W.C. “The bryophyte flora of the east coast
of Hudson Bay,”
Bryologist
, vol.46, pp. 73-87, 1943.
99. Zetterstedt, J.E. “Musci et Hepaticae Finmarkiae circa sinum Altensem
crescentes,” Svenska Vetenskapsakad.
Handl
. vol.13,
[:
]
no.13, pp. 1-42, 1876.
William Campbell Steere