288 Alexander IV. Evans, 



teeth smaller: spores (according to Stephani) yellowish brown, 

 23/1. in diameter, erose along the ridges, otherwise smooth. 

 (Fig. 14.) 



Known only from the following specimens: 

 Brazil : Rio Janeiro, A. Glaziou 6348 (B., N. Y., type) ; E.Ule 

 123 (B., listed by Stephani in Bull. Herb. Boissier 7 : 406. 1899). 



The material of M. Bescherellei in the Boissier herbarium, por- 

 tions of which have been examined by the writer, includes the 

 female type specimens and the male specimens collected by Ule. 

 A sterile specimen of the type material, in the Mitten herbarium, 

 has likewise been examined. It will be noted that Spruce,^* who 

 published a list of Glaziou's specimens, makes no mention of 

 No. 6348. According to the label on the specimen in the Mitten 

 herbarium. Spruce thought that this number might perhaps 

 represent a new genus of the Marchantiaceae, but he evidently 

 reached no definite conclusion about it. Probably he had only 

 sterile material at his disposal, because the female receptacle 

 shows at once that Stephani was correct in referring the plant 

 to the genus Marchantia. Unfortunately the specimens studied 

 by the writer were very fragmentary and remained shriveled after 

 long soaking in water. It was therefore impossible to gain from 

 them an adequate idea of the species, and some of the statements 

 made about the structure must be regarded as more or less 

 tentative. 



The texture of M. Bescherellei is exceedingly delicate and the 

 thallus thins out abruptly in passing from the midrib to the 

 wings. In the latter the ventral tissue becomes reduced, accord- 

 ing to Stephani, to a single cell in thickness, and the marginal 

 portion, where the entire thallus is only one cell thick, is four 

 cells broad. Although the air-chambers are low the photosyn- 

 thetic tissue is well developed and characteristic and the pores 

 are large and complex. 



The appendages of the ventral scales are composed of cells 

 which show a gradual decrease in size in passing from the median 

 portion toward the margin, resembling in this respect the appen- 

 dages of M. domingensis and M. papillata, but the margin itself is 



Rev. Bryol 15 : 33, 34- 1^ 



