2 o 8 Shiv Ram Kashyap. 
last three are found at a level of about 5,000 feet, Metzgeria being 
an epiphyte. 
The following is a list of the thallose forms met with at 
Mussoorie at a level of 6,000 feet (with the exception of the three 
species mentioned above). The position of the new genera and 
species is briefly indicated, as full descriptions are given later. The 
methods by which these plants pass through the dry period are 
indicated by letters : A indicates the ability of the plant to revive 
as a whole after desiccation ; B indicates that the apical part only 
survives, but is not much modified ; C that the apex is modified to 
form a definite tuber; D that ventral or lateral shoots are modified 
to form tubers. The rest are hygrophilous or annuals. It must be 
also mentioned that reproduction by spores plays a very unimportant 
part in this region. 
(1) Riccia discolor (B). (2) Targioniahypophylla(A). (3) Cyatho- 
diuni tuberosum , sp. nov. (C). Male receptacle of composite type. (4) 
Aitchisoniella himalayensis , gen. et sp. nov. (B). Near Targionia but 
female shoot reduced to receptacle. (5) Athalamia pinguis Pale. 
(Trans. Linn. Soc., vol. 20, 1851) (B). Near Clevea. (6) Gollaniella 
pusilla St. (Hedwigia, vol. 44, 1905) (B). (7) Plagiochasma 
appendiculatum (A). (8) P. articulatum, sp. nov. (A). Receptacles 
terminal, growth continued by an adventitious shoot. (9) Reboulia 
hemispherica (A). (10, 11, 12) Fimbriaria, three species (B). (13) 
Grimaldia californica (A). (14) Exormotlieca Uiberifera , sp. nov. 
(D). Ventral shoots form tubers. (15 )Stephensoniellabrevipeduncnlata, 
gen. et sp. nov. (C). Near Exormotlieca but growth continued by an 
adventitious apical shoot after formation of female receptacle. (16) 
Cryptomitrium himalayensis , sp. nov. (C). (17) Dumortiera hirsuta, 
hygrophilous. (18, 19) Marchantia, two species, in shady moist 
places. (20) Aneura pinguis, in shady moist places. (21) 
Metzgeria hirsuta, sp, nov. (A). (22) Pellia calycina, in moist 
places. (23) Fossombronia himalayensis, sp. nov. (C). (24) Sew ardiella 
tuberosa, gen. and sp. nov. (C). Very near Fossombronia but thallose. 
(25) Notothylas sp. Annual. (26) Anthoceros himalayensis, sp. nov. 
(D). Ventral and lateral shoots form long-stalked tubers. (27) 
Anthoceros erectus, sp. nov. Annual, with large mucilage cavities. 
(28) Massalongoa tenera, described by Stephani (Hedwigia, Bd. 
44, 1905), but not found by the writer. 
The general conclusions arrived at by the writer with regard 
to the evolution of the Marchantiales in the light of the new species 
may be set forth in a few lines. The detailed discussion will be 
