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the commencement of the apophysis, which does not differ in appearance
from the rest of the theca. Calyptra paie, at first mitriform, at length
dimidiate. L id conical, with a very slight acumination. Peristome of
16 equidistant, yellow, linear-lanceolate, transversely striated teeth,
united at the extremities, and each marked by a longitudinal line down
the centre. Columella exserted, as in the genus Splachnum, dilated towards
the mouth of the theca, and then contracted to the summit : it is
frequentiy so attached to the lid as to retain it for a considerable period
after it has separated at the mouth of the theca. Sporules globose,
greenish, appearing dotted and reticulated under the microscope.
In regard to the history of this, one of the most interesting
and rare of Scottish mosses, I feel that I cannot present my
readers with one correct or more concise, than that which my
friend Dr H o o k e r has recently given in the New Series of
the Flora Londinensis. “ Our acute cryptogamist Mr D ic k so
n ,” says Dr H o o k e r , “ seems to have been the first to have
discovered, in Scotland, and to have described this plant in the
fourth fasciculus of his “ Plantæ Cryptogamiccrf under the
name of Splachnum lingulatum. The Swedish botanists next
appear to have found it, and to have examined its characters ;
and it has appeared in different publications as the Weissia
splachnoides of Sw a r t z ’s MSS. (S m . in F n g l. Bot.), of
T h u n b e r g ’s m s s . (Schzvaegr.), and of W a h l e n b e r g ’s (see
Fl. Fapp.) S m i t h , in the Flora Britannica, has confounded
our moss with the Splachnum tenue (the Splachnum longicol-
lum of D ic k s o n ), and has adopted Sw a r t z ’s name, only
changing the Weissia into Grimmia. In Fnglish B o tany
the figures with the ripe capsules (received from Dr S w a r t z )
will be found to belong to our plant ; but the others, and especially
the magnified leaf, will be recognised, at once, as belonging
to tbe Splachnum tenue. A t t. 2095. of the same work,
our true plant appears under the name of Splachnum lingulcr-
tum. Lastly, it has been published by S c h w a e g r ic h e n in
his Supplement to H e d w ig ’s Sp. Muscorum, as Weissia
splachnoides, a name it seems now generally to have retained.”
As Dr H o o k e r has already noticed, in the splendid work
from which we have extracted the above account, the eiTors in
the representation of our plant in tbe Muscologia Britannica,
and wbicli, indeed, must be attributed to imperfect specimens,
it would be needless to dwell on tbe subject in this place, as they
will be rectified in tbe second edition, so anxiously expected.
A great discrepancy of opinion exists as to tbe genus of this
moss;—there can be none as to its natural relations, which are
clearly those of the Splachnoid Family. In the course of some
extensive examinations of the genera of Mosses, by Mr W a l k
e r A r n o t t and myself, we had arrived at the conclusion
that it was absolutely necessary to remove this plant from the
genus Weissia, and to form a new one, in order to receive it.
Our observations, however, not having been published, the
name recently proposed by Mr R o b e r t B r o w n * will have
tbe right of priority. H e has named his new genus C y r t o -
DON ; but his notice of it being merely incidental, and without
a character, I have followed Dr H o o k e r in keeping up the
old name, more as a matter of convenience than from a conviction
of its propriety.
Dr H o o k e r has correctly observed, that there is nothing
in tbe calyptra of our plant which can keep it separate from
Splachnum, as, in most of the species of the latter genus, the
calyptra eventually splits up on one side, and renders it as
much dimidiate as tbe one in question. The greatest objection,
however, to our moss being retained in the genus Weissia,
unquestionably arises from the structure of the peristome, the
teeth of which are divided by a longitudinal line to the very
base, as in Aplodon Wormskioldii (which in fact is just as
much a Weissia as Weissia splachnoides, the teeth being
equidistant, and 16 in number). I am not aware of such a
structure occurring in a true Weissia, while it approximates
our plant most closely to the Splachnoid Family, where probably
in no instance is it wanting, whether the teeth be equidistant
or in pairs.
The columella only differs from that of the Splachna, in
having a longer narrow portion above the dilated summit,
which is on a level with the mouth of the theca; the narrow
• B r o w n , i n Suppl. t o P a r r y ’s F i r s t V o y a g e , p . c c x c i x . u n d e r A p l o d o n .