IO 



once his basket with fish remains. On the contrary, he will 

 search long and well before finding a trace of these animals. On 

 the other hand, he will usually have no difficulty in obtaining all 

 the fossils he cares to take home, but they will be shells, not 

 fishes. In the Chemung rocks from Binghamton westward there 

 are certain layers of rock almost made up of the remains of one 

 little animal, Spirifer disjunctus (see PI. XI, fig's 87, 88), a 

 brachiopod that flourished during the Chemung period and then 

 became extinct. Other brachiopods represented by Pi's. XI and 

 XII are in places very common. 



The true mollusks were well represented in the Chemung, as 

 Pi's. IX, X and XI testify. Of these the lamellibranchs (Pi's. 

 IX and X) were by far the most numerous. Cephalopods and 

 gastropods were comparatively scarce. 



Kchinoderms were represented by a few crinoids and other 

 rarer forms. Bryozoans and corals are locally abundant, but gen- 

 erally scarce. The same remark applies to the sponges. Trilo- 

 bites, and other crustaceans generally, are very scarce. 



Fragments of plants are of quite common occurrence, though 

 identifyable specimens are rare. They belong to tree-ferns and 

 tree-lycopods. 



Of the Portage group, the Ithaca beds are characterized by 

 a brachiopod fauna, whereas the Naples beds to the west are 

 characterized by cephalopods, fishes, lamellibranchs and gas- 

 tropods. 



