BRITISH JUNGERMANNIA. 
C J. Hookcri.) 
Like the seeds, the spiral filaments are in a young state green, and enclosed in a thin 
white membrane (f. 12), which in their perfect state is lost. They are formed of a single 
helix, attenuated at each extremity, and, as in most of the frondose species, are attached 
to the extremity of the valves in pencil-shaped tufts. 
Perhaps, there is not to be found, in the whole genus of Jungermannia, a species more decidedly 
marked, both in its fructification and its foliage, than that represented on the annexed plate. It is 
one of the many interesting discoveries made by Mr. Lyell, who kindly proposed that it should bear 
the name under which it has been already described in English Botany. 
The most remarkable feature in this plant, (if I may be allowed such an expression, where 
every thing is so strange,) is the absence of a calyx, and the prominent fleshy calyptra, which, by 
a casual observer, might be taken for a calyx. The horizontal, thick, and fleshy fibres of the root, 
seem rather to belong to some phaenogamous plant, than to the genus Jungermannia, almost all the 
species of which are furnished with remarkably slender, simple, and descending radicles. The multifa- 
rious insertion of the leaves is of rare occurrence in the present tribe of plants. Indeed, I am only 
acquainted with two species of British origin which have this peculiarity in common with it, 
J. setacea and trichophylla ; but in every other respect, these plants are widely different; the 
individuals now mentioned having setaceous leaves, while those of J. Ilookeri are broad and 
subovate, or ligulate, varying most remarkably in size, and in the shape and situation of the lobes 
and crenatures, with which the margin is generally furnished. Most of the Jungermannia: are 
well known to possess the property of being easily restored to a fresh and vigorous appearance, after 
being dried for a considerable length of time : but the present species is a striking exception even to 
this rule, since, after ever so long an immersion in water, it very imperfectly recovers its original 
state. 
In the color of the Anthers, and in their exposed situation, a similarity may be traced between 
them and the Anthers of J. pusilla. But the female fructification is totally different, and, in the 
form of the capsule and the situation of the spiral filaments, there is a close analogy with 
J. pingitis and multifida, between which, and the Jungermannia foliosce, J. Ilookeri may be 
considered as holding the middle rank. The cohering of the apices of the valves of the capsule, 
which Mr. Lyell has remarked to be an equally common occurrence in the specimens he finds at 
Kinnordy, as in those from the New Forest, is not confined to this species : it also happens with 
the capsule of J. Lyellii. But in no other individual have I yet observed the seeds to be disposed in 
threes, within a pellucid covering ; though, it is not impossible that such a circumstance may 
have escaped my notice, through neglect of examining the capsules in an immature state, when 
this appearance is most ‘evident. 
