354 
MUSCINEM. 
2. The family Monocleae appears, according to the ' Synopsis Hepaticarum,' to 
contain transitional forms between the Anthoceroteae and the Jungermannieae. The 
long sporogonium has a longitudinal dehiscence and no columella ; and the sexual 
generation is either thalloid or foliose. 
3. The RiccieaB form a flat dichotomously branched thalloid stem, floating in 
water or rooting in the ground, the apical cells of which, lying close to one another 
Fig. ■2-i%.—Anthoceros lavis ; the young sporogonium, the letters point to the foot ; L the invohicre ; 
c—c the columella (.after Hofmeister, X 150). 
in the anterior depressions of the branches, are stated by Kny td become multiplied by 
vertical longitudinal partitions, and segmented by walls inclined upwards and down- 
FlG. ■2y).—Rjccin glmica; A vertical longitudinal section through the apical region; s apex, b leaves, a young an- 
theridium, a' older antheridium already surrounded by involucral tissue lu ; B rudiment of an antheridium a already 
overarched ; C young antheridium a in longitudinal section (after Hofmeister, x 500). 
wards. On the upper side a distinct epidermis is differentiated, but without stomata, 
and beneath this lies the green tissue often provided with air-cavities, which is derived 
from the upper segments of the apical cells ; the under side is provided with a single 
longitudinal row of transverse lamellae, which, resulting immediately from the lower 
segments of the apical cells, must be considered as leaves. Afterwards they split length- 
