92 COLLEMACE^ OF THE NORTHERN STATES 



Rocks (especially limestone, Ach.). Pennsylvania, Muhl. in herb. 

 Willd. ! The specimen appeared to me to agree with an original one 

 from Acharius. Schserer refers the species to C. flaccidum. It is 

 said to occur in Massachusetts. 



12. C. pulchellum, Ach. Th. membranaceous, orbicular, plane, 

 somewhat laciniate, round-lobed at the circumference, plicate-papulose 

 and dark-green above, beneath paler and deeply lacunose ; apotb. 

 crowded, elevated, the disk urceolate, pale, the margin thin, coarctate, 

 very entire, at length somewhat rugulose. Ach. Syn. p. 321. 



Trunks and rocks. New England. Pennsylvania, Muhl. ! Ohio, 

 Mr. Lea ! 



13. C. saturninum, Ach. Th. rosulate, blackish-green, glaucous 

 and subtomentose beneath, the lobes broad, oblong, rounded, waved, 

 very entire ; apoth. scattered, somewhat plane, rufous, with a thin, en- 

 tire margin. Ach. Syn. p.Z2Q. Hook. Br. Fl. 2, p. 211. Exs. Schar. ! 

 Helv. 423. 



Trunlcs and stones. New England. Arctic America, JlicA. I have 

 omitted several species of this genus, which require more observation. 



II. LEPTOGIUM, Fr. 



Apothecia rounded, becoming discoid-open and scutelliforra, some- 

 what pedicellate, with a proper exciple. Thallus gelatinous-membra- 

 naceous, subdiaphanous, texture cellulose. 



1. L. Tremelloides, Fr. Thallus foliaceous, membranaceous, very 

 thin and somewhat diaphanous, smooth on both sides, or powdery above, 

 lead-colored ; lobes oblong, rounded, very entire ; apothecia scattered, 

 elevated, plane, rufous-fuscous, with a paler margin. Fr. Fl. Scan. p. 

 293. Collema, Ach. Hook. Br. Fl. 2, ;;. 213. 



Rocks and trunks, New England. New York, Torrey. Pennsylva- 

 nia, Muhl. 



2. L. lacerum, Fr. Th. foliaceous, membranaceous, very thin and 

 somewhat diaphanous, glaucous-fuscescent, the lobes small, subimbri- 

 cate, lacerate-laciniate, denticulate-ciliate ; apoth. (small) scattered, 

 subsessile, somewhat concave, rufous, with a paler margin. Fr. ! Fl. 

 Scan. p. 293. Collema, Ach. Hook. Br. Fl. 2, p. 213. 



On the earth, and rocks, among mosses. New England. New 

 York, Halsey. Pennsylvania, Muhl. 



