234 M- LECIDEACEAE [ 128. Lopadium 



spatulate; spores acicular to somewhat fusiform, 3-7- or 9-septate, 24-50 X 

 2.5—5 fx. 



On soil and rocks, Washington and California. 



7. Toninia Candida (Web.) T. Fries, Kgl. Svensk. Vet. Akad. Handl. 7:33. 1867. 

 Lichen candidus Web., Spic. Flor. Goett. 193. 1776. Lecidea Candida (Web.) 



Ach. Diphloeis Candida. (Web.) Clements. 



Thallus composed of middle-sized, swollen, lobulate, powdery, whitish to white 

 squamules, sometimes crowded into an uneven or wrinkled crust ; apothecia mid- 

 dle-sized to large, 0.8-2 mm. across, adnate, irregular, the disk flat, grayish prui- 

 nose, the exciple thin, grayish pruinose, becoming flexuous; hypothecium brown; 

 spores fusiform, 1-septate, 16-23 X 2-4.5 fx. 



On soil, Utah. 



8. Toninia aromatica (Turn.) Mass., Fram. Lich. 24. 1855. 



Lichen aromaticus Turn., Linn. Trans. 9:140. 1808. Lecidea aromatica Turn. 



Thallus composed of small, thick, closely clustered or more or less scattered, 

 greenish gray to brownish or ashy squamules, the squamules sometimes running 

 together into a thick, warty, irregular crust; apothecia small to middle-sized, 0.4-1 

 mm. across, adnate, often irregular and clustered, the disk flat to convex, black, 

 the exciple thin, black, soon disappearing; hypothecium brown to blackish brown; 

 spores fusiform, 3-septate, 15-27 X 3-4.5 /a. 



On mosses over rocks, Minnesota and California. 



128. Lopadium Koerb., Syst. Lich. Germ. 210. 1855. 



Thallus crustose, granulose or warty, rudimentary, devoid of differentiation 

 into layers and attached to the substratum by hyphal rhizoids; apothecia rarely 

 minute to small or middle-sized and large, sessile, the disk flat to more or less 

 convex, light-colored to black, the exciple thin to thick, usually colored like the 

 disk, often disappearing; hypothecium hyaline to brown or black; hymenium 

 hyaline to brownish; paraphyses usually unbranched and somewhat coherent; asci 

 clavate or cylindrico-clavate; spores 1-8, hyaline, transversely and longitudinally 

 sepate. 



The algal host is Protococcus. 



A. On leaves, mosses, and rocks 



B. On leaves; apothecia pale brownish to greenish and 



finally black 7. L. phyllocharis 



B. On mosses and rocks; apothecia reddish yellow to dirty 



orange, sometimes grayish pruinose 6. L. fuscoluteum 



A. On trees 



B. Spores rarely more than 50 n in length 



C. Apothecia small, 0. 25-0. S mm. across 1. L. Augustini 



C. Apothecia larger, more than 0.5 mm. across 



D. Spores 1-4 in each ascus, 1-3-septate longitudinally ... 3. L. vulpinum 

 D. Spores 2-8 in each ascus, 1-septate 



longitudinally 2. L. domingense 



B. Spores commonly more than 60 fi in length 



C. Apothecia black 4. L. pezizoideum 



C. Apothecia yellow or rust-colored to dark green . . . 5. L. leucoxanthum 



1. Lopadium Augustini (Tuck.) Zahlbr., Cat. Lich. Univ. 4:299. 1926. 



Heterothecium Augustini Tuck., Syn. N. A. Lich. 2:59. 1888. 



Thallus thin, often scanty, granulose, greenish gray; apothecia minute to small, 

 0.25-0.5 mm. across, sessile, the disk flat to slightly convex, blackish, the exciple 

 thin, hanging, white; hypothecium reddish brown; spores 1, long oblong-ellipsoid, 

 9-13-septate transversely and 3-5-septate longitudinally, 40-60 X 14-20 /x. 



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



