292 Dr. John T. Plummer on the > 



of some species of Gorgonia. To the naked eye they have the 

 appearance of ordinary fucoides ; but under a glass of considera- 

 ble magnifying power, the structure mentioned is very obvious. 



Fig. 7. 





I know that in perhaps most instances no organized structure is 



possi 



while the 



general form is p 



statement to excite others to further microscopic examinations of 



these fossils. 



Radiaria 



few 



encrinites 



and still more rarely, equally small pentacrinal joints. 



which 



species 



Favosites 



Clifford^ of which I have discovered but a single specimen ; fre- 

 quently specimens of Eschara, and a few species of Astrea, of 

 Calamopora, and of Cosinopora. Most of these fossils are ex- 

 ceedingly common, and when broken in the rock, easily arrest 

 the attention by their white interior. A step-stone at my door, 

 with a surface of six square feet, exposes sections of eighty one 

 Cyathophyilse. The poras mentioned, are strewed every where 

 along our river banks. The Eschara is perhaps confined to the 



"marlite." 

 Bivalves. 



three other species : 



have two species of Delthyris ; the 

 semiovalis, S. deltoidea, and I think 

 rthis testudinaria. and two other spe- 



cies ; a small Pentamera ; the Atrypa Wilsoni, and one other 

 species ; several species of Pterinea ; two species of Avicula ; a 

 very rare species, which, as far as the shell is exposed, has the 



