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beautiful of known mosses ; here both the peristome and endostome are
broken up into a brush-like tuft of cilia, and there is no epiphragm. In
both these genera we recognise a certain affinity to Buxhmmia by the
depressed, ovate and somewhat irregular capsule, and again the scabrous
seta of Buxbaumia is represented in the Malayan Racelopus, a feature quite
exceptional in this family, where it is usually polished and wiry.^ ^ Lindberg’s
paper “ Observationes de formis presertim earopæis Polytriclwidearum, in Notis. ur
Sallsk. pro Fn. et Fl. fenn. forh. ix, p. 91 (1867), is perhaps the most perfect
example of a botanical dissertation which has ever come before us.
In this a very curious relation existing between the peristome and
epiphragm is pointed out and used to divide the genus Polytrichmn into two
sections Pterygodon and Leiodon, but as the parts are very minute and would
offer difficulties to students in their examination, we have preferred the older
divisions of C. Mueller.
A part of this beautiful combination was first accurately made known
b y our celebrated countryman Richard Spruce in his paper on “ The Mosses
and Hepaticoe of the Pyrenees,” in Trans. Bot. Soc. of Edinburgh, iii, 162 (1849) ;
and as these structures are so important, it may be of interest to quote the
descriptions of both authors.
Spruce says,— “ In Polytrichmn alpinum the epiphragm is originally placed
at the base of the teeth, to which it is attached by means of processes equal
to diem in number, and exactly covering their internal face. After the fall
of the lid, these processes are gradually detached, and the epiphragm rises,
probably from the pressure of the full-grown spores beneath it, so as to allow
the latter to escape through the interstices of the peristome. When the
epiphragm is quite liberated, the processes curve inward upon its upper
surface, so as to be with difficulty seen, unless the light be properly regulated,
or the epiphragm be set up on its edge. The adhesion of the epiphragm to
the teeth is so great as to resist the action of the columella to draw it down
into the capsule, and often ultimately to cause the columella to rupture.
Lindberg’s description is as follows,— “ In the Polytrichaceæ the teeth
are incurved and in transverse section triangular, especially at the base ; the
inner surface of the teeth is elevated in the middle into a longitudinal crest,
which is composed of the innermost cells of the basal membrane not reaching
the apex of the tooth. The apices of these cells in the subgenus Pterygodon
are not united to the teeth, but inflexed, free or irregularly connected with
each other, and form wings, compressed at the sides, and resembling stag’s
horns. These wings are formed both from the basal membrane itself, and
the lower part of the crests of the teeth, and are somewhat coloured or
hyaline; they enclose chambers of the same number as the teeth, in the
mouth of the capsule, the fundus of which is formed by the basal membrane,
the walls by the teeth and their wings, and the roof by the epiphragm ; these
spaces are fenestræ for the exit of the spores, when the spore sac finally
bursts at apex. Th e species referred to Pterygodon are P . commune, juniperinum,
strictum and piliferum, and in these also the epiphragm is thin, flat and strictly
contained between the apices of the peristome, to which it closely adheres by
the margin. From its lower surface and within the margin, hang down
sacculi or nipple— like processes, closing the upper part of the interdental
spaces, almost to the middle of the teeth, and as many in number as the
interspaces. In the young state, these mamillæ reach down to the basal
membrane, but in the mature fruit contract by drying, and the spore sac also
rupturing, through these apertures, as in the fruit of Pafaver and Camfamda,
the spores escape. The remaining species form the subgenus ¿« » ¿« and m
this as well as in Catharinea and Oligotrieham the wing-like crest is wanting, the
epiphragm is thick, concave, and generally somewhat hollowed m the centre,
the margin toothed with thin processes curved upward and inward, and
closely fixed to the upper part of the teeth, which they resemble in structure.
For this reason the epiphragm is not strictly contained within the apices of
the peristome, but hangs down from them for the length of the dentiform
processes, connate with the highest part of peristome. Maniillæ are also
absent from the under surface, and the spores are much larger.
The leaves of Polytrichaceæ, except in Catharinea and Racelopus, are
thick and opake, from the presence on the upper surface of numerous longitudinal
lamellæ, and the number and structure of these lamellæ, as seen in
transverse section, are as Prof. Lindberg points out, of the greatest importance
for a proper discrimination of the species, especially in the barren state ;
the cells forming their free margin are particularly to be noted, as they vary
considerably in different species.
In Catharinea the lamellæ are few and confined to the nerve, and are
chlorophyllose like the leaf lamina, but in Polytrichum the lamellæ alone
have chlorophyllose cells.
Pogonatmn is not separable from Polytriclmm as a natural genus, for
in a large proportion of species referred to Pogonatmn (forming the section
Anasmogonium M it t.) , the capsule is 6— 8 plicate, while in some Polytrieha
the angles of the capsule are almost obsolete.
It may be noted that Pol. commune is one of the few mosses which have
been put to economic purposes. Linnæus tells us that the Laplanders use
it for beds, and commends it as not harbouring fleas or any infectious disease ;
in the north of England it is also made into small dusting brooms and mats.
I . C A T H A R IN E A E h r h a r t .
(Hannov. Mag. 1780, 59 Stück, p. 933 ; et Beitr. i., pp. 126 et 178 (1787).
Plan ts mnioid, gregarious or ccespitose, throwing up e re c t stems
from a creeping, subterranean rhizome. L e a v e s lingulate or oblong,
generally undulated, crisped when dry ; bordered and serrate at margin ;
the nerve with few lamellæ ; areolation chlorophyllose, rounded—
hexagonal. C a lyp tra narrow, cuculla te, spinulose only at apex.
Capsule oval or cylindric, subarcuate ; annulus none ; lid convex, long-
beaked ; teeth of peristome 32, lingulate, rigid, with a narrow basal
membrane ; sporangium close to the w a ll o f capsule ; spores minute,
smooth. Inflorescence usually dioicous ; the male cup-like, with
numerous bra cts and filiform paraphyses.
This genus was founded by Ehrhart in honour of Catharine II. Empress
of Russia, and for the reasons stated under Georgia, yet Schimper displaces it