105. Leptogium] 28. COLLEMACEAE 167 



23. Leptogium palmatum (Huds.) Mont., in Webb & Berth., Hist. Nat. Canar. 



3 2 :128. 1840. 



Lichen palmatus Huds., Fl. Angl. ed. 2. 535. 1778. 



Transforming the algal colony into a middle-sized or larger, irregularly cut- 

 lobed, sharply wrinkled and pitted, lead-colored to chestnut-brown body, becoming 

 narrow, involute, tubular toward the ends, with toothed margins; paler and 

 wrinkled below; apothecia minute to small, 0.2-0.5 mm. across, sessile, crowded, 

 the disk concave, reddish brown, the algoid exciple thin, paler than the disk, 

 slightly elevated; hypothecium hyaline to cloudy; spores ovoid, 5-7-septate trans- 

 versely and 1-3-septate longitudinally, 30-52 X 12-18 /x. 



On soil among mosses, from Texas to Colorado, and westward to California 

 and Washington. 



24. Leptogium californicum Tuck., Syn. N. A. Lich. 1:159. 1882. 



L. californicum var. lophotum Tuck. L. scotinum var. platynum Tuck. 



Transforming the algal colony into a rather large, finely and sharply wrinkled 

 and often granulose, irregularly lobed to sometimes erectly branched, marginally 

 dilated, elongated and crenate, ascending, bluish to blackish brown body; apothecia 

 small to middle-sized, 0.4-0.8 mm. across, sessile, the disk slightly concave, reddish 

 brown, the proper exciple thick and brownish; hypothecium hyaline to cloudy; 

 spores ovoid-ellipsoid, 5-9-septate transversely and 1-3-septate longitudinally, 

 30-54 X 11-19 yu.. 



On rocks, California. 



25. Leptogium platynum (Tuck.) Herre, Proc. Wash. Acad. Sci. 12:144. 1910. 

 L. californicum var. platynum Tuck., Gen. Lich. 96. 1872. 



Transforming the algal colony into a middle-sized to large, round, appressed, 

 irregularly lobed, finely striate or wrinkled, more or less pustulate, black or green- 

 ish black body, the lobes elongated, expanded, imbricate, with crenate or dentate 

 margins; paler and finely wrinkled below; apothecia minute to small, 0.2-0.5 mm. 

 across, sessile, the disk concave, reddish brown, the exciple thin and elevated, 

 paler than the disk; hypothecium hyaline to cloudy; spores ellipsoid, 7-9-septate 

 transversely and 1-3-septate 'longitudinally, 28-52 X 10-17 /x. 



On soil and rocks, in moist places, California. 



26. Leptogium scotinum (Ach.) E. Fries, Corp. Fl. Prov. Suec. 1:293. 1835. 

 Lichen scotinus Ach., Lich. Suec. 128. 1798. L. scotinum var. sinuatum (Huds.) 



Forss. 



Transforming the algal colony into a small, round or irregular, wrinkled, cut- 

 lobed, lead-colored to brown body, the lobes round, crowded, suberect, with entire 

 to subcrenate margins; apothecia minute to small, 0.2-0.5 mm. across, sessile, 

 scattered, the disk concave, reddish brown to brown, the proper exciple slightly 

 elevated, colored like the disk or paler; hypothecium hyaline to cloudy; spores 

 ovoid to ellipsoid-pointed, 7-9-septate transversely and 1-5-septate longitudinally, 

 24-40 X 8-15 fi. 



On soil, southern California. 



27. Leptogium lichenoides (L.) Zahlbr., Cat. Lich. Univ. 3:136. 1924. 

 Tremella lichenoides L., Sp. PI. 1157. 1753. L. lacerum (Swartz) S. Gray. 



L. lacerum var. lophaeum (Ach.) Koerb. 



Transforming the algal colony into a middle-sized, more or less round, reticu- 

 larly wrinkled, irregularly lobed, greenish brown to lead-colored body, the lobes 

 ascending, expanded toward the ends, and divided into jagged or fringed margins; 

 scarcely lighter below; apothecia small, 0.3-0.6 mm. across, subsessile and rare, 

 the disk concave to flattish, reddish to reddish brown, the algoid exciple rather 

 thick, colored like the thallus, entire; hypothecium hyaline to cloudy; spores ellip- 

 soid, 5-11-septate transversely and 1-3-septate longitudinally, 26-50X11-18^. 



Among mosses on rocks and on trees, throughout the United States. 



