312 Alexander W. Evans, 



more than five lobes, these being more or less elongated ; and 

 tlie involucre is very delicate in texture, the margin varying from 

 crenulate to short-ciliate. 



The features which distinguish M. chenopoda from M. domin- 

 gensis will distinguish it also from the South American M. 

 papillata. Another South American species to which it may be 

 related is M. Bescherellei, the appendages and involucres of 

 which might easily come within the range of variability exhibited 

 by M. chenopoda. According to our present knowledge, M. 

 Bescherellei is a more delicate species with lower air-chambers 

 and thinner ventral tissue. There is no danger of confusing M. 

 chenopoda with any of the other species recognized in the present 

 paper. 



Doubtful Species 



1. Marchantia squamosa Raddi ; Lehm. & Lindenb. in Leh- 



mann. Pug. Plant. 4: 12. 1832 (as to the Brazilian plant). 



Brazil : without definite locality or date, Raddi. 



Attention has already been called to this species and to its 

 possible aggregate nature (see p. 261). Stephani's description 

 agrees in most respects with M. paleacea, and it is possible that 

 Raddi's specimens would now be referred to that species. If 

 this should prove true it would mark an interesting extension of 

 range. 



2. Marchantia quinqueloba Nees, Naturg. Europ. Leberm. 



4:98- 1838. 



West Indies: without locality, date, or collector's name. 



According to the full description given by Nees von Esenbeck 

 this species is probably a form of M. domingensis. In any case 

 there seems to be no reason for attempting to maintain it, since 

 the original specimens (according to Stephani) are poorly 

 developed and valueless. 



3. Marchantia pusilla Nees & Mont. ; G. L. & N. Syn. Hep. 



526. 1847. 



Chile : without locaHty, date, or collector's name. 



This species was based on a single very immature specimen and 

 is not represented in the Montagne herbarium. The original 

 description throws little light on its affinities, and Montagne him- 



