(J. undulata .) 
BRITISH JUNGERMANNIiE. 
of the stem; the upper one, or lobule*, is smaller by one half: they are both of a 
roundish figure, sometimes a little pointed, slightly waved or undulated, the margins 
entire, or at most obscurely crenate in a few of the terminal ones. The texture is, for 
so large a plant, peculiarly thin and delicate ; the reticulation small, composed of 
roundish cellules. The color varies from its most usual appearance of dark and dull green, 
with often a purplish tinge, to deep purple, and even almost to black. 
The Perigonial Leaves (f. f. 4. 9) are scarcely distinguishable from the common cauline 
ones, except that they are more crowded and imbricated; their base, too, is somewhat 
ventricose. They are situated at or near the extremity of a stem. 
Perichatial Leaves (f. 6) somewhat larger than the rest, which they in other respects 
resemble, and are, like them, either entire, or slightly crenate ; but so slightly as to be 
visible only with a microscope. 
Male Fructification (f. 9) situated in the axil he of the perigonial leaves. Anthers (f. 10) 
small, in clusters of from three to five or six, each of them ovate, pellucid, faintly reticulated, 
filled with a greenish pollen ; the footstalk somewhat longer than the anther, white, pellucid, 
and transversely jointed. 
Female Fructification (f. f. 2. 3. 6) terminal upon the stems and larger branches. 
Calyx (f. 6) about two lines long ; its base is narrow, attenuated, and cylindrical, thence 
it becomes broader, compressed and incurved towards the mouth, which is truncate and 
entire. As the fructification advances, the calyx becomes nearly erect. In color it 
resembles the leaves. Its substance is less delicate. 
Calyptra oblong, somewhat pyriform, with a short tubular style, and a few barren pistilla 
at its base. 
Peduncle half an inch long, white, shining, cellulose, often having a twisted appearance, 
terminated by the ovato-oblong 
Capsule of a deep brown or chocolate color, which splits into four equal, nearly lanceolate 
valves. 
Seeds and Spiral Filaments (f. 7) much resembling those of J. nemorosa ; but the filaments 
are scarcely so much lengthened. 
Upon the summit of Ben Nevis, in the month of July, I found Gemma (f. f. 12. 14) upon 
this species, collected together in ovate masses, one or two of which were situated in the terminal 
cluster of leaves : their color was a pale yellow green ; each particle was oblongo-ovate, pellucid 
and entirely free from angles. 
Vaillants description and figure, above quoted, are so imperfect, that, as Dr. Smith justly 
observes, they cannot with certainty be referred to any thing. His account of the gemma;. 
* Some of the terminal leaves, as is remarked by DiUenius, have the upper lobe nearly of the same size as the under 
one ; but this appears to me to apply only to such as have not reached their full size, and are almost concealed by the 
older surrounding ones. } 
