American Species of Marchantia. 261 



he maintained still more definitely that M. paleacea and M. nitida 

 were identical and stated further that in his opinion M. nepalensis 

 also would have to be considered a synonym.^" He criticised 

 Stephani for placing M. paleacea in one section of the genus, 

 while he placed M. nepalensis and il/. nitida in another, thus 

 implying that their relationship to the Italian species was at best 

 remote. 



The writer would agree with Schiffner in his reductions. Type 

 specimens of M. papillata ft italica, of AI. nepalensis, and of M. 

 nitida have all been available for study. The first and third are 

 in good condition and show close agreement with each other 

 and with the abundant material of AI. paleacea from other locali- 

 ties. The type specimen of AI. nepalensis bears very immature 

 female receptacles, but the thallus characters are those of AI. 

 paleacea and there seems to be no reason for attempting to main- 

 tain the species as valid. Two other species quoted above among 

 the synonyms of AI. paleacea remain to be considered. The first 

 of these is AI. squamosa. Wallich's specimens of tliis species 

 are clearly the same as AI. paleacea, and since these specimens 

 are the ones first quoted by Lehmann and Lindenberg, they might 

 logically be considered the type. It is probable, however, that 

 Raddi originally gave the name AI. squamosa to his own Bra- 

 zilian specimens, and this is apparently the view held by Stephani 

 who quotes only the specimens from Brazil. Raddi's specimens 

 have not been seen by the writer. If they should prove distinct 

 from AI. paleacea it might still be possible to maintain AI. 

 squamosa as valid. It is unfortunate that Raddi published 

 nothing on his species himself. The second species to be con- 

 sidered is AI. planipora, which the writer knows from a portion 

 of the type material and from specimens sent by Professor 

 Miyake. These specimens agree with M. paleacea, and the 

 descriptions given by Stephani bring out no essential differences. 



There is usually little difficulty in distinguishing AI. paleacea 

 even in the absence of receptacles. At the present time it is the 

 only known North American species in which the epidermal pores 

 constantly conform to the cruciate type. In this respect it agrees 

 with AI. Berteroana of the Southern Hemisphere, a much larger 

 plant with very different scale-appendages and terete rays on the 

 female receptacle. Aside from the cruciate pores M. paleacea 



' Lotos 49 : 92. 1 901. 



