112 
[Assembly 
Testacea. 
Pileopsis tubifer, S. , 
compressa, G 
ventricosa, C. 
vetusta, S , 
Pentamerus Knightii, S. . . . 
Atrypa concentricaj Brown, 
affinisj S 
Leptsena depressa, S 
punctuliferaj C. 
indenta, C. 
unguiformisj C. 
Delthyris resupinata, S 
pachyoptera, G. 
cycloptera, C. 
bilobata, C. 
Peterinea alseforme, S 
Conularia quadrisulcata, S. . 
Orthoceras inflatum, 
Crustacea. 
Cytherina, 
Calymene bufo. Green, .... 
platys, G. 
anchiops, G. 
Asaphus selenurus, Eaton, 
laticostatus, G. 
micrums, G. 
3. The third group has been termed " Calciferous slate'^ by Eaton. 
It is a gray limestone shale, containing all the gypsum beds of the State. 
Org'anic remains are very rare, except on the Genesee river, where no 
gypsum occurs. The lower part contains a thin stratum of limestone, 
made of broken valves of a pentamerus. This is the only instance of 
shells broken by attrition that has come under our observation through- 
out the whole transition order. Above the pentamerus, the well known 
trilobite Asa'phus caudatus is abundant. The group is equivalent to the 
" dye earth" of Shropshire, which is characterized by the trilobite above 
mentioned. 
Organic Remains of the Third Group. 
Plants. 
Fucoides serratus. 
European localities. 
, . . . . near Clithero. 
Eifel. 
Plymouth. 
Yeo Edge, Downton, Eifel. 
Tournay. 
Dudley, 
do 
Dovedale. 
Eifel. 
Gloucestershire. 
Eifel. 
Coalbrookdale. 
