348 
MU SCI NE JE. 
leaves and lateral shoots, since Leitgeb's researches show that great morphological 
differences occur in the different genera. For the same reason very little of a 
general character can be said, in addition to what has been mentioned above, on 
the habit and anatomical nature of the vegetative body, which must therefore be 
considered under the separate families. 
The Asexual Propagation of Hepaticse is often brought about by the dying off 
of the thallus or stem from behind, the branches thus losing their connexion and 
becoming independent. Adventitious branches, arising in the thalloid forms from 
cells of the older marginal parts, become detached in a similar manner. The 
propagation by gemmcE is very common and characteristic ; not unfrequently a 
number of cells of the margin of the leaf of foliose Jungermannieae [e.g. in Mado- 
thecd) simply detach themselves as gemmae ; in Blasia, on the other hand, as well as 
in Marchaniia and Lunulan'a, peculiar cupules are formed on the upper side of the 
flat shoots exposed to the light, which are flask-shaped in Blasia, broadly cup-shaped 
Fig. ■223.—Marrhantia polyniorfha ; yJ , B young 
shoots ; C the two shoots which result from a gemina, 
with cupules ; v v the depressed apical region : D a 
piece of the epidermis seen from above : sj> stomata 
on the rhomboid plates (A—C X slightly: D more 
strongly). 
Fig. 234.— Development of the gemmae of 
Marcha7Uia. 
in Marchaniia, crescent-shaped and deficient on one side in Lunularia. From the 
bottom of these cupules shoot out hair-like papillae, the apical cells of which be- 
come transformed into a mass of considerable size constituting the gemma. (See 
Figs. 233, 234.) From the two depressions which lie right and left on the margin 
of the lenticular gemma (Fig. 234, VI) spring the first flat shoots (Fig. 233, B, C), 
when the gemmae have fallen out of the cupule and lie exposed to light on damp 
ground. 
The Sexual Organs are developed, in the thalloid forms, on the upper side 
exposed to light; in Anthoceros in the tissue of the thallus itself (endogenous); in 
the other thalloid forms from cells which project like papillae and are of definite 
origin in reference to the segments of the apical cell. In the Marchajitieae branches 
of a very peculiar shape, which have a tendency to shoot upright from the flat 
stem, are formed, producing the antheridia on the upper, the archegonia on the 
under side ; the male and female receptacles may be distributed either monoeciously 
