142 
IOWA ACADEMY OF SCIENCES. 
Peltigera canina (L.) Hoff m. var. sorediata (Schaer.) Tuck. 
Syn. North Amer. Lich. 1:109. 1882. 
On shaded rock and sandstone, rare. 
Peltigera canina (L.) Hoffm. var. spuria (Ach.) Tuck. Syn. 
North Amer. Lich. 1:109. 1882. 
On earth, rare. 
Pannaria nigra (Huds.) Nyl. Lich. Scand. 126. 1861. 
On sandstone, abundant. 
Amphiloma (Pannaria) laguinosa (Ach.) Nyl. Prod. Lich. 
Gall. et. Alg. 69. 1857. 
On sandstone, abundant. 
Collema pulposum (Bernh.) Ach. Syo. Lich. 311. 1814. 
On sandstone, rare. 
Senechoblastus (Collema) nigrescens (Ach.) Stitzenb. Beit, 
zur Flechtensyst 144. 1862. 
On trees and sandstone, rare. 
Leptogium lacerum (Sw.) Nyl. Syn. Lich. 1:122. 1858. 
On mossy sandstone, rare. 
Leptogium pulchellum (Ach.) Nyl. Syn. Lich. 1:123. 
1858. 
On trees, rare. 
Leptogium chloromelum (Sw.) Nyl. Syn. Lich. 1:128. 
1858. 
On mossy rocks, rare. 
Placodium cibrinum (Hoffm.) Leight. Lich. PI. Great 
Brit. 177. 1871. 
On sandstone, rare, (Thallus and fruit larger and 
darker than usual.) 
Placodium aurantiacum (Lightf.) Naeg. and Hepp. 
Spor. der Flecht. Eur. 1853. 
On sandstone, common. 
Placodium cerinum (Ehrh.) Naeg. and Hepp. Spor. der 
Flecht. Eur. 1853. 
On trees, common. 
Placodium cerinum (Ehrh.) Naeg. and Hepp. var. sider- 
itis Tuck. Syn. North Amer. Lich. 1:175. 1882. 
On granite, rare. 
