Trcjxtticfr of XorfJi Aiiirrlcd. 23 



neath; divisions narrow, dichotomous, plane or when dry 

 broadly canaliculate above, convex-thickened beneath; lobes 

 nearly linear, very obtuse, narrowly emar<jfinate and somewhat 

 thickened at the apex; rootlets smooth within; antheridia 

 large, immersed, causing the under surface to appear nodulose. 

 Possibly only the male plant of No. 1. 



ITab.— Nev. ( Watson), Col. ( Wolfe). 

 Bib.— Torrey Bull. YI, p. 17. 



8. R. glauca L. Thallus orlncular, soiuewhat stellately 

 lobed, 1.3 — 2.5 cm. in diameter; divisions linear-obovate or 

 linear-obcordate, emarginate-lobed, channeled only toward the 

 apex^ heaut'ifidhj reticulate and glaucous abore.^ membranous 

 along the margin, greenish beneath; spores 0.084 mm. in diam- 

 eter, moderately reticulate and with a narrow pellucid margin. 



Hab.—Ca\. (Bolander). (Eu.) 



Bib.— Syn. Hep. p. 599, Hep. Europ. p. 167. 



Delin. — Lindenberg Monog. Eic. t. XIX. 



4. R, albida Sulliv. in Herb. 1853. Thallus small, cov- 

 ered with a thick, spongij, deeply-pitted, milk-white epidermis, 

 alternately or bifurcately divided; divisions oblong, much 

 croAvded, with a rounded sub-marginate apex, narrowly and 

 deeply canaliculate above, densely radiculose and sul)squamous 

 beneath; fruit unknown. 



Hab.—TeJi. (^Wright). 



Bib.— Fro. Phil. Acad. 1869, p. 231. 



5. R. Beyrichiana Hampe, MS. Thallus fleshy, caespi- 

 tose, adhering to the earth by long hyaline rootlets, sensibly 

 dilated from a narrow linear base, mostly bifid ^ the length, 

 narrowly channeled and green above, the margins entire, as- 

 cending. Clothed with a dark-purple membrane beneath. 



Hab. — " Between Jefferson and Gainsville, Tenn." (Beyrich). 

 Bib.- -Syn. Hep. p. 601. 



0. R. bifurca Hoffm. Thallus dichotomously or sub- 

 stellately divided, pale green; divisions wedge-shaped, 2-lobed 

 at the apex; lobes spreading, dotted, broadly channeled al)ove 

 by the thick and ascending margins, purpli.sh beneath. 



