1904) FINK—A LICHEN SOCIETY 271 
Cladonia gracilis dilatata (Hoffm.) Wainio, occurring with the last; rare. 
These forms have not been recognized before in Iowa, but have been included 
under the partial synonym var. hybrida Fr. 
Stereocaulon paschale (L.) Ach. (?), on exposed and little disintegrated rock, 
but better developed toward the basal, damp, and more disintegrated portions 
of the riprap extensions. Small and perhaps as near S. coralloides. A northern 
species new to Towa. Frequent, but only once seen in fruit. 
Lecanora cinerea (L..) Sommerf. ( ?), on exposed and comparatively firm rock; 
once seen and sterile. : 
Lecanora muralis saxicola (Poll.) Schaer., occurring as the last; once seen and 
Placodium aurantiacum (Lightf.) Naeg. and Hepp, on firm rock of the riprap 
wall; once seen. 
Placodium vitellinum (Ehrh.) Naeg. and Hepp, on firm and exposed rock; 
rare, 
eee corinne (Ehrh.) Naeg. and Hepp (?), occurring as the last and 
rare; spores immature. 
Acarospora (Lecanora) cervina juscata (Schrad.) Fink; once seen on firm rock 
of the northward-facing wall : 
Acarospora (Lecanora) xanthophana (Nyl.) Fink, on exposed and firm rock; 
once seen and sterile. 
Mestina sophodes (Ach.) Kbr.; once noted on a firm and exposed spot where 
aoe Was especially hard because of the presence of a large amount of iron. 
1 rapid field work the plant is not easily distinguished from the first of the list 
and _— be somewhat more common than appears at present. 
i Ach., on exposed rock, rare and easily passed over for the 
Siete muralis Ach., on exposed and comparatively firm surfaces; rare. 
P. juscella Fr., occurring with the last and more rare. 
1a Borreri Turn., on quite firm, but somewhat damp and shaded rock; 
rare and sterile, 
a conspersa (Ehrh.) Ach., occurring as the last and also very rare and 
Physej . 
wall hyscia stellaris (L.) Tuck., once seen on the shaded, northward-exposed 
R : ia 
Ward ——< calicaris (L,.) Fr., on damp surfaces toward the base of the north- 
facing wall; once seen. 
Me of the r _ (Endocar pon) pusillum Hedw., on somewhat shaded rocks of 
‘- "ptap extensions; very rare. 
id . : 
mh eg thirty forms listed above, there occurs commonly a 
"osum (fj "NS somewhat like that of Amphiloma (Pannaria) lanugi- 
8 2). This thallus is without distinct cortex and seems 
Y as rudj 
Tudimentary as that of Amphiloma, but is verrucose rather 
