244 Alexander W. Evans, 



pared with the other specimens cited above. The epidermal cells 

 are unusually delicate and are slightly smaller than the averages 

 given, measuring perhaps i8 x io/a, but the epidermal pores and 

 ventral scales agree very closely with those of the other speci- 

 mens. It is clear, therefore, in the writer's opinion, that all the 

 specimens cited represent the same species. 



The original material of M. lamellosa has not been available 

 for study, but the specimen from Colombia, listed above, was 

 referred to this species by Mitten and is evidently the same as 

 the specimens from Ecuador, Peru, and Bolivia. On the basis 

 of this specimen and the full description in the Synopsis Hepati- 

 carum, M. lamellosa is here reduced to synonymy. It should be 

 noted, however, that Stephani considers it valid, so that this 

 reduction is perhaps unwarranted. He ascribes to the species 

 cruciate pores and papillate rays on the female receptacles. In 

 one of the Peruvian specimens. No. 672, some of the pores are 

 as cruciate as those of M. oregonensis, but other pores are not 

 cruciate at all, so that a considerable range of variation is present. 

 The lack of receptacles in these specimens makes it impossible to 

 determine whether papillate rays are associated with pores which 

 approach the cruciate condition, although the constant absence 

 of papillae in all the fruiting specimens studied, which are clearly 

 the same as No. 672, makes such an association improbable. 

 Even if papillae occasionally occurred they would hardly afford a 

 basis for a specific separation. Stephani cites M. lamellosa from 

 the type locality and also from Ecuador (Chimborazo and Altar, 

 Hans Meyer) .^^ He cites M. plicata from the type locality, from 

 Ecuador (Quito, Ortoneda, Spruce), from Colombia (Lmdig), 

 and from Venezuela (Merida, Moritz). It is probable that the 

 Lindig specimens are those listed by Gottsche under M. poly-, 

 morpha and that the Morifz specimens are those doubtfully 

 referred by Hampe^® to M. Berteroana. Of course, in the 

 absence of the specimens themselves, this matter can not be 

 definitely decided. 



Although M. plicata and M. polymorpha are closely related 

 species it is usually easy to distinguish them. Some of the dif- 

 ferential characters, however, are vague and subject to varia- 

 tion. When M. plicata is well developed the thallus and the 



" See Meyer, In den Hoch-Anden von Ecuador 517. Berlin, 1907. 

 " Linnaea 20 : 333. 1847. 



