Hepaticw of North America. 25 



Bab. Rocky ground; N. Y. (Torrey], Chester, Pa. (Porter], Cal. 

 (Bokmder). (Eu.) 



Bib. Syn. Hep. p. 605, Hep. Europ. p. 170. 

 Delin. Lindenberg Monog. Ric. t. XXIX. 

 Exsic. Hep. Bor.-Arner. No. 140 b. 



*** Thallm more or less ciliate on the margins, naked or obso- 

 letely squamous along the extreme edge underneath; usually 

 with a purple spot in the epidermis immediately over the 

 fruit. 



10. B. arvensis Aust. Thallus always orbicular, radi- 

 ately much divided, 0.6 1.8 cm. in diameter, dull green both 

 sides, papillose-reticulate and becoming fuscous above; margins 

 plane, entire, acute or apparently thickened, becoming purple 

 by age; divisions often crowded, somewhat dilated above from 

 a common base, dichotomous, distinctly sulcate, carinate-thick- 

 ened especially toward the apex, nodulose beneath; lobes linear- 

 elliptic or subspatulate, acutish and obsoletely emarginate at the 

 apex" cilia white, very short or often papilla-like and incon- 

 spicuous ; fruit aggregated beneath the canal chiefly toward the 

 apex of the lobes; spores about 0.071 0.084 mm. in diameter, 

 dark fuscous, slightly pellucid, distinctly reticulate, with a con- 

 spicuous pellucid margin. 



Var. hirta Aust. Thallus decidedly ciliate on the margin, 

 and with spine-like hairs scattered over the whole upper sur- 

 face, at length purple and more or less squamigerous beneath, 

 somewhat glaucous and reticulate above; divisions broader, 

 more obtuse, becoming thin and strongly canaliculate or often 

 convolute on drying; spores nearly black, larger, 0.084 0.101 

 mm. in diameter, opaque, very indistinctly reticulate, and ob- 

 scurely papillose, obscurely if at all margined. 



Hob. Rocky ground and cultivated fields; Closter, N. J. (Austin). 

 The var. in similar locations. 



Bib Pro. Phil. Acad. 1869, p. 232. 

 Exsic. Hep. Bor.-Amer. Nos. 141, 142. 



11. R. Lescuriana Aust. Monoecious; thallus stellately 

 or somewhat cruciately divided; divisions bilobed or di-trichot- 

 omous, obcordate or cuneate-linear, 0.4 1.3 cm. long, punctate- 

 reticulate, somewhat glaucous or cinereous green and slightly 



