American Species of Marchantia. 



289 



very different in being much more sparingly toothed. Among the 

 preceding species the appendages find their closest counterparts in 

 M. paleacea and M. breviloha. Their apices, however, are more 

 uniformly sharp-pointed, their teeth tend to be sharper, and their 

 marginal cells are more frequently placed at right angles to the 

 margin. 



With regard to the female receptacle there are marked dis- 

 crepancies between Stephani's original description and the later 

 description of his Species Hepaticarum. According to the orig- 



FiG. 14. Marchantia Bescherellei Steph. 



Anatomical details. A-C. Appendages of ventral scales, x 100. 

 Part of an involucre, x 100. Drawn from the type specimen. 



D. 



inal account the disc is green, convex in the middle, five-lobed for 

 one third the distance from margin to center, the lobes being 

 rounded and shortly incised at the apex, plane and horizontal, 

 delicate and beautifully reticulated. Doubt is thrown, however, 

 upon the constancy of the five-lobed condition. The involucres 

 are described as reddish, firm in texture, and shortly ciliate. 

 According to the later account the disc is brownish green, delicate 

 and veiny, plano-convex in the center, and nine-lobed, the lobes 

 being plane, connate almost to the apex, rounded and very shortly 

 incised. The involucre is said to be hyaline, small-lobed, irregu- 

 larly and shortly fimbriate. In the only receptacle seen by the 

 writer the disc is five-lobed, the two basal lobes being only about 



