EURYPTERUS. 



PPP. 29 



other evidence in a fragment of a large somite which is too 

 imperfect to be usefully illustrated. The specimen, Fig. 10, 

 presents the inner surface of a fragment of some large crusta- 

 cean, which is broken and incomplete along the upper mar- 

 gin, as shown in the figure. This may, perhaps, have been a 

 portion of a large ectognath of some sj)ecies of this famih'. 

 In addition to the above mentioned forms, Mr. C. E. 

 Beecher has placed inmy handsfor description a well-marked 

 species of Eurypterus from a sandstone of the Chemung 

 group at Warren, Pennsylvania. This species is the first 

 one noted from this horizon and is of considerable interest. 



Tabular view^ of the Geological Distkibutiox of 

 the family eurypteridie in the united states. 



