( J . corilifolia.J 
BRITISH JUNGERAIANNIrE. 
The Perigonial leaves, which extend from the apex of a stem to nearly half way down its 
length, scarcely differ from the rest, except in having their base more concave. 
The Perichcetial leaves are also, in every respect, like the cauline ones. 
Male Fructification. Anthers situated in the axillae of the perigonial leaves, large in 
proportion to the size of the plant, exactly spherical, reticulated, placed upon a short, pellucid, 
transversely striated footstalk. On pressing one of these with an instrument, while under the 
microscope, an extremely minute pollen, or granulated substance, was dischaiged, each particle 
of which was roundish, angular, and semitransparent. 
Female Fructification both terminal and arising from the axillae of the branches. 
Calyx oblongo-ovate, much lengthened out at the base, the upper part slightly plicate, 
the mouth small and very indistinctly toothed. 
Germen ovate, dark green. 
Barren pistilla eight or ten in number, linear, longitudinally striated. 
The present is one of the most distinct of the British Jungermanniae with which I am 
acquainted, nor can I mention any to which it bears the smallest affinity, either in the form of its 
leaves, or in the singular manner in which they embrace each other with their involute margins. 
The color too is very peculiar, being extremely dark, so that, when seen in tufts, it appears 
almost black. By immersion in water for a few hours, a deep brownish tinge is imparted 
to the liquid. 
In the form of the calyx this species approaches J. minuta, but the calyx here is shorter in 
proportion to its diameter, and less plicate ; the leaves of the two plants are very unlike, and so 
strikingly are those of the present species heart-shaped (when they are expanded, as at f. 6), 
and so much do they in their general direction resemble those of Hypnum cordifolium, that I have 
thought that the same specific name would also be applicable to the Jungermannia as to 
the Hypnum. 
Mr. Dickson was probably the first person who gathered this plant; since I find it among a 
number of unnamed species that he has been so good as to send me, which were collected many 
years ago in the Scotch mountains. Mr. Woods has since gathered it in Ireland, and Mr. Lyell 
and myself in Scotland. 
