Hepaticw of North America. 37 



deciduous, more or less scale-like fragments; peduncles 2.5 cm. 

 high, rather delicatel}^ cellular, pale above, pvirplish below, 

 naked. (Marchantia fenera Hook., Duralia fenera Gottsche, 

 T). j)cdunrulata Mont.) 



Hab. — Cal. (Parry, Bigelow, Bolander, Torrey). 

 Bib.— Syn. Hep. p. 554. 



VII. ASTERELLA Beauv. 



Carpoceplialum conic-hemispheric, becoming flattened, 1-6 

 (usually 4)-lobed, barbulate-palaeaceous beneath. Outer invo- 

 lucres 1-fruited, coherent with the lobes, 2-valved. Inner in- 

 volucre wanting. Calyptra minute, lacerate, persistent at the 

 base of the capsule. Capsule greenish, globose, nearly sessile, 

 rupturing at the apex by irregular narrow teeth, or by a frag- 

 mentary operculum. Spores tuberculate. Elaters moderately 

 long, mostly bispiral. Inflorescence monoecious; androecium 

 sessile, lunate-disciform. Thallus rigid, very indistinctly po- 

 rose, the midrib broad, strong and distinct. Name the diminu- 

 tive of Lat. a strum, a star, alluding to the mature carpocepha- 

 lura. 



1. A hemisphserica Beauv. Thallus forking and in- 

 creasing by joints from the extremities, rather pale-green above, 

 purple beneath: carpoceplialum papillose on the summit, di- 

 minishing greatly by age; peduncle bearded at its base and 

 apex^ at first 2 — 2.5 cm. long, increasing often to 5 — 7.5 cm. 

 after maturity of fruit. [RehouUa hemispluerica Raddi, R. mi- 

 crocephahi Tayl. ) 



Hah. — Shaded banks chiefly along sti'eams ; common. (Eu.) 

 Bib.—^yn. Hep. p. 548, 790 ; Hep. Europ. p. 154. 

 Delin.—^xjiWiw. Mosses U. S. t. VI. 

 Exsic. — Hep. Bor.-Amer. No. 132. 



VII. DUMORTIERA Nees. 



Carpoceplialum convex above, 2-8-lobed. Involucres 1- 

 fruited, opposite and connate with the lower surface of the 

 lobes, horizontal, opening by a vertical slit at the outer extrem- 

 ity. Inner involucre wanting. Calyptra rupturing at the apex. 



