PYXINE. 79 



1. P. picta (Sw.) Tuckerm. Thallus softish, closely aggluti- 

 nate to the substrate/ radiately plaited, white - glaucescent j 

 beneath black, scarcely fibrillose ; lobes confluent, flattened and 

 pinnately many-cleft at the circumference, but passing finally at 

 the centre into a wrinkled-warty crust, often besprinkled with 

 rounded, white soredia j apothecia small, sessile, the vinous-red 

 disk soon becoming black, and now pruinose, at length scarcely 

 exceeded by the sub-crenulate margin. Spores bilocular, ^J 



mic. Obs. Lich. 4, 1. c.p. 166. Physcia, Nyl. Syn. I, p. 430, 



.& t. 8, /. 53. Parm. applana'ta, Fee ; Mont. Cuba, p. 223, t. 8, /. 

 1. Tuckerm. Obs. Lich. 1, I c.p. 398. 



* erythrocardia, Tuckerm. ; thallus saffron-coloured within. 



Trees, and dead wood in the low country of South Carolina 

 (Eavenel), Tuckerman in Nyl. Enum.'lS5S, of Georgia, Eavenel; 

 of Louisiana, Hale] Texas, Wright] and Mexico; as also on 

 rocks, in Alabama, Peters. * erythrocardia, in Texas, Eave- 

 nel. Differenced from Physcia by its hypothecium, but suffi- 

 ciently agreeing in this, as in general -aspect, with Pyxine] 

 which, in P. Meissneri, offers apothecia not always well distin- 

 guishable from those of the present. Parmelia confluens, Fr. ; 



united by Nylander with the earlier P. cegialita, Ach., should, 

 with little doubt, be referred here : at least no difference appears 

 to be noted. 



l(b). P. Frostii^ Tuck., thallus crustaceous, closely adnate, 

 stellate-radious, smooth, from glaucous-grey becoming cream- 

 coloured ; beneath black ; divisions sub-palmately cleft, convex, 

 concrete (besprinkled commonly with white soredia) ; apo- 

 thecia small, sessile j the disk flat, black ; the margin incurved. 



Spores bilocular, ^ mic. Squamaria, Suppl. 1, 1. c., p. 425, 



dein Lecanora. 



Granitic rocks, New England (Frost) Tuckerman Suppl. 1858. 



Harper's Ferry, Virginia, Tuckerman. Rarely observed in 



fruit ; the want of which has heretofore obscured the affinity of 

 the lichen. It is a greatly reduced, 'northern exhibition of the 

 preceding tropical species. l 



1 And a still more marked reduction of this type is presented by a 

 lichen from volcanic rocks of the Galapagos Islands (Dr. Hill in Hassler 

 Exp.) in which while the apothecia offer no differences unless possibly 

 rather smaller spores, the thallus has passed wholly into convex, glebous 

 Creoles, somewhat lobed only at the circumference (P. glebosa, Mihi, 

 herb.}. 



