No. 200.J 115 
Testacea. European localities. 
Pleurotomaria cirriformis, S. . , Plymouth. 
Bellerophon apertus, S Eifel. 
Conularia quadrisulcata, S , .... Gloucestershire* 
Spirula constricta, G . 
Orthostoma communis, C. 
Trocholites ammonius, C. 
Phragmolites compressus, C. 
Orthoceras duplex, W. 
striatum, S Christiania, 
Delthyris, striatula, G EifeL 
micropteraj G....... ....... do. 
pectinoides, C, 
Leptsena deltoidca, C. 
alternata, C. 
semiovalis, C. 
Lingula ovata, €. 
Crustacea. 
Isotelus gigas, Dekay. 
Cyclops, Green. 
Calymene Elumenbachii, Brong, ....... Dudley* 
Cryplolithas tesseltatus, Green,. Llandeilo, 
Ceraurus jDleurexanthemus, G, 
Paradoxides Beckii, Hall. 
Asaphus micropleums, G. 
The last named trilobite has not been found entire. The abdomen 
and tail closely resemble those of calymene tuberculatus. 
It is a curious fact, that whilst the Calymene Blumenbachii, ceased 
to exist in New-York after the final deposition of the Trenton series, it 
escaped into remote seas, and lived in the era of the Dudley limestone. 
The Cryptolithus tessellatus on the contrary, seems to have existed, 
and to have become extinct, at the same periods in the seas which de- 
posited the rocks of Llandeilo and Trenton falls. The plants and Crus- 
tacea are peculiar to this group, and of the testacea, I have observed but 
two species in a superior formation; Delthyris striatula and a small Or- 
this resembling O. crumena, but having invariably four plaits or ribs on 
the mesial elevation. Of the polyparia, one only has been noticed 
above the present series; Cyathophyllum cerutites. All these fossils oc- 
cur in the second group, in the limestone of the Helderberg mountain. 
