IOWA ACADEMY OF SCIENCES. 
145 
Buellia spuria (Schaer.) Arn. Flora. 291. 1872. 
On rocks. (Tending toward Buellia lepidastra , as 
margins of apothecia are more or less evanescent 
and thallus is quite as near that of the latter.) 
Buellia parasema (Ach) Kbr. Syst. Lich. 228. 1855. 
On trees, rare. 
Buellia myriocarpa (D. 0.) Mudd. Man. Brit. Lich. 250. 
1861. ~ 
On old wood, frequent. 
Opegrapha varia Ach, Lich. Univ. 259. 1810. 
On trees, infrequent. 
Graphis scripta (L.) Ach. Lich. Univ. 265. 1810. 
On trees, common. 
Arthonia lecidella Nyl. Enum. Cener. Lich 337. 1858. 
On trees and sandstone, frequent. 
Arthonia radiata (Pers. ) Th. Fr. Lich. Arc. 240. 1860. 
On trees, common. 
ArthotheKum spectabile (Flk.) Stiz. Beitr. Flechtensyst. 
152. 1862. 
On trees, infrequent. 
Calicium quercinum Pers. Tentam. dispos. Fung, suppl. 
59.1797. 
On trees, rare. 
Calicium quercinum, tending toward var. subcinium. 
Nyl. Syn. Meth. Lich. 8:156. 1858. 
On trees, rare. 
Calicium parietum Ach. in Veg. Acad. Eandl. 260. 1816. 
On red cedar, rare. 
Dermatocarpon (Endocarponl pusillum (Hedw.) Schnei- 
der. Text. Licht. 189. 1897. 
On sandstone, rare. 
Yerrucaria nigriscens Pers. in UIs. Ann. de Bot. 14:36. 
1795. 
On sandstone, frequent. 
Yerrucaria viridula Ach. Lich. Univ. 675. 1810. 
On granite, rare. (Thallus of the characteristic color 
but too scanty to be certain that it is not Y. nigres- 
cens.) 
New to Iowa. 
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