2 10 
Shiv Rain Kashyap. 
Cyathodium Tuberosum Kashyap. 
In shape and structure the thallus is like that of C. cavernarum 
as described by Lang. The species under consideration, however, 
is dioecious and forms tubers. Thus the plants are met with in 
three forms—sterile, male, and female. The sterile plants are once 
or twice dichotomously divided and the lobes are linear or linear- 
oblong. The appearance of the male plants is variable, the lobes 
being linear or oblong obcordate. The female plants may be linear 
or linear-oblong, but more often they are fan-shaped with many 
growing points on the anterior margin due to rapid dichotomy. 
The narrow plants are usually less than 2 mm. broad, while the 
large female plants may be as much as 1 cm. long and 2 cm. broad 
in favourable localities. The plants are usually found in dark and 
moist places forming dense masses of overlapping individuals. In 
some cases the only other plant inhabitant of the cave was 
Cryptomitrium himalayensis Kashyap, and under these circumstances 
both these species have a yellowish phosphorescence. Cyathodium 
tuberosum may, however, occur in only slightly shady places along 
with Riccia, Targionia, Plagiochasma, Anthoceros and other more 
or less xerophilous forms and even in almost exposed situations, 
where it develops a deep green colour. 
In some sterile and smaller male plants no pores are ever 
formed. In a large number of them, however, pores are present 
but on the ventral surface. In the larger female plants pores are 
present on the dorsal surface. Pores on both surfaces were not 
met with in any plant. The dorsal pores (Fig. 1, a) are scattered 
on the dorsal surface, one being found in one but not in every 
areole ; they are circular just behind the anterior margin but 
become elongated and elliptic further back. Each pore is surrounded 
by two or three series of four or five cells each ; these cells are 
narrow and hyaline and peculiar in that the outer walls of the 
innermost cells are also concave outwards like the inner walls. 
The transition to the ordinary cells of the thallus is gradual. The 
ventral pores are much simpler and much larger and elongated in 
the direction of the longitudinal axis of the thallus (Fig. 1, b). They 
are bounded by ordinary cells of the thallus. All the cells of both 
the upper and lower layers of the thallus contain chloroplasts but 
they are more numerous on the dorsal side. 
There are two rows of scales on the ventral surface. They 
may be simple cell rows or small plates (Fig. 1 , c, d). Usually 
there are no mucilage cells but occasionally a small cell differing 
