166 28. COLLEMACEAE [105. Leptogium 



18. Leptogium bullatum (Ach.) Mont., Ann. Sci. Nat. II. 16:113. 1841. 

 Lichen bullatns Ach., Lich. Suec. 137. 1798. 



Transforming the algal colony into a middle-sized to large, irregularly lobed 

 or nearly entire, rigid, wrinkled, dull blue to lead-colored, marginally ascending 

 and often folded body; apothecia middle-sized to large, 1-2 mm. across, sessile to 

 subpedicellate, the disk concave to nearly flat, red, the exciple algoid and colored 

 like the thallus, becoming lobed; hypothecium hyaline to brownish; spores ovoid- 

 pointed, 3-5-septate transversely and 1 -septate longitudinally, 24-36 X 8-14 /a. 



On trees, South Carolina, Florida, and Texas. 



19. Leptogium phyllocarpum (Pers.) Mont., Ann. Sci. Nat. Bot. III. 10:134. 



1848. 



Collema phyllocarpum Pers., Gaud. Voyag. Uran. 204. 1826. L. bullatum var. 

 phyllocarpum (Pers.) Tuck. 



Transforming the algal colony into a small to middle-sized, strongly wrinkled, 

 irregularly lobed, lead-colored body, the lobes round, wavy, or variously cut; paler 

 below; apothecia middle-sized to large, 1-2.5 mm. across, sessile, the disk concave, 

 dull red to brownish, the proper exciple brownish, thin, surrounded by a heavy, 

 folded, and wavy algoid one; hypothecium hyaline to cloudy; spores ovoid to 

 ellipsoid, 3-5-septate transversely and becoming 1-septate longitudinally, 23-34 X 

 6-12 fi. 



On trees, Florida and Texas. 



20. Leptogium crenatellum Tuck., Am. Journ. Sci. II. 28:200. 1859. 

 Transforming the algal colony into a small to larger, dilated, umbilicately 



attached, greenish gray, yellowish, brownish, or ashy squamulose body, with as- 

 cending, smooth lobes and wavy to crenate margins; apothecia small to middle- 

 sized, 0.5-1 mm. across, sessile, the disk flat to slightly convex, reddish, the 

 proper exciple thin, colored like the thallus, crenulate, finally disappearing; hypo- 

 thecium hyaline to brownish; spores ovoid-ellipsoid, 3-septate transversely and 

 becoming 1-septate longitudinally, 16-22 X 7-9 /x. 

 On trees, in swamps, Vermont and Illinois. 



21. Leptogium marginellum (Swartz) S. F. Gray, Nat. Arr. Brit. PI. 1:401. 



1821. 



Lichen marginellus Swartz, Nov. Gen. et Spec. PI. 147. 1788. 



Transforming the algal colony into a middle-sized, more or less strongly and 

 reticulately wrinkled, cut-lobed, lead-colored body, the lobes becoming branchlike 

 with folded, curled, entire to subentire margins; apothecia minute, 0.1-0.25 mm. 

 across, borne on the margins of the lobes, sessile, the disk flat, brownish to reddish 

 brown, the proper exciple rather thick, pale to brownish, somewhat granulose, and 

 becoming narrowly lobed; hypothecium hyaline to cloudy; spores ovoid to ellip- 

 soid, 3-5-septate transversely and becoming 1-septate longitudinally. 20-30 X 

 10-12 jx. 



On trees, Florida, Alabama, Louisiana, and Texas. 



22. Leptogium pulchellum (Ach.) Nyl., Mem. Soc. Sci. Nat. Cherb. 5:90. 1857. 

 Collema pulchellum Ach., Syn. Lich. 321. 1814. 



Transforming the algal colony into a middle-sized to large, closely adnate or 

 marginally ascending, delicately folded and wrinkled, irregularly lobed, lead-colored 

 body, the lobes imbricated, round with wavy margins; lighter-colored below, and 

 more or less pitted and wrinkled; apothecia middle-sized to larger, 0.7-2 mm. 

 across, sessile to shortly stalked, the disk flat to slightly convex, reddish brown 

 to brown, the algoid exciple thin and colored like the thallus ; hypothecium hyaline 

 to brownish; spores ellipsoid or ellipsoid-pointed, 5-septate transversely and 1-3- 

 septate longitudinally, 18-30 X 8-14 /*. 



On trees and rocks, from Vermont to Florida, and westward to Texas and 

 Washington. 



