COLLEMA. 147 



Trees, not uncommon from New England to Virginia, Tuck- 

 erman I. c. 1863. New York, Eussell. South Carolina, Eavenel. 



Alabama, Peters. Louisiana, Hale. Texas, Wright. As also- 



in Cuba, Wright ; and Japan, Wright. 



9. C. microptychium, Tuckerm. ; thallus small, pulvinate, car- 

 tilagineous; blackish-green; lobes thickly crowded together, 

 erectish, rounded, crenate, gyrose-complicate ; apothecia small, 

 sessile, flat ; the disk rufous, the margin entire. Spores vermi- 

 form, plurilocular, decolorate, ^^ mic. Lich. Calif, p. 35. 



Trunks of Elm, Chestnut, and other trees, Amherst, Mass. r 



Tuckerman 1. c. 1866. As C. leptaleum offers the thallus of C. 



aggregatum with distinct spores, the present lichen exhibits 

 the spores, we may say, of C. leptaleum with an irreconcilable 

 thallus, now approaching that of the next specie.s. A rather 

 larger but not dissimilar lichen, differenced similarly to this 

 from C. flaccidum by its thicker thallus, has occurred, on trees, 

 at Amherst, and in the White Mountains, Tuckerman j Willey ; 

 but always infertile. 



10. C. flaccidum, Ach.; thallus middling-sized, membrana- 

 ceous ; olive -green ; made up of ample, lax and bullate, rounded, 

 entire lobes, which are besprinkled mostly with concolorous 

 granules, and the ascendant margins plicate-undulate ; beneath 

 paler ; apothecia smallish, scattered, sessile, flattish ; the disk 

 reddish-brown, the thin margin entire, now granulate. Spores 

 ovoid and cymbiform, 4-6-locular, decolorate, ^ mic. ; becom- 

 ing also long-fusiform, and 6-8-locular, ^^ mic. Ach. Syn. p. 



322. Tuckerm. Gen. p. 91. 



Kocks and trunks, from New England to Virginia, Tucker- 

 man Syn. N. E. 1848. Canada, Drummond. Ohio, Lea. Illi- 

 nois, Hall. North and South Carolina, infertile, Eavenel ; New 

 Mexico, infertile, Fendler. 



11. C. nigrescens (Huds.) Ach. ; thallus middling-sized, or- 

 biculate, thin-membranaceous, sub-monophyllous, closely ad- 

 nate to the substrate, smooth, conspicuously marked with radi- 

 ating wrinkles, and pustule-like prominences ; olivaceous-green 

 and blackening; the rounded, flexuous lobes entire; beneath 

 paler, costate-lacunose ; apothecia small, crowded; the disk 

 reddish-brown, becoming convex and excluding the thin mar- 

 gin. Spores long-fusiform and acicular, plurilocular, decolorate,, 

 4 -g? mic. Ach. L. U. p. 646. Nyl. Syn. 1, p. 114. 



