BULL 'Z Tl-N 



BUFFALO SOCIETY OF MTDRAL SCIENCES. 



VOLUME III. 



I. Description of a New Crustacean from the Water 

 Lime Group at Buffalo 



BY AUG. E. GJIOTE AND W. H. PITT. 



[Eead before this Society, July 2, 1875.] 



The impression of tlie ventral surface of a Crustacean is 

 exposed in the specimen of a r\"w form allied to Earypterus 

 and PterijgoUis^ for which the name Eusarcus SCORPIONIS is 

 proposed. The cephalothoracic iiortion appears to be separate 

 from the body, and to be considerably narrower in proportion 

 than in allied forms. The legs are in the same number as in 

 Euryjpterus. The swimming feet appear to difl'er by the 

 straighter, less rounded outer margins. In the specimen the 

 rhomboidal plates are not given. From the impressions of the 

 joints of the swimming feet their relative dimension does not 

 seem to accord with Etwypterus. The four pair of anterior 

 feet proceed from two elongate oral plates of which the impres- 

 sion is very distinct. The spines of the anterior feet appear to 

 be long, curved, and to have an .i^.terior direction. The absence 

 of chelate appendages to the posterior margin of the feet is par- 

 ticularly noticeable. The first seven broad segments of the 

 abdomen form a large ellipse. There is an evident and remark- 

 able narrowing of the succeedhig caudal segments. Of these 



BUL. BUF. 80C. NAT. SCI. (1) JULY, 1875. 



