ACERATA—MEROSTOMATA. 407 



13. E. myops Clarke. (Fig. 1713,/,^.) Siluric. 

 Small; head subquadrate, nearly as square in front as behind; 



eyes large, semicircular. 



Shawangunk conglomerate of New York. 



14. E. pittsfordensis Sarle. (Fig. 1706.) Siluric. 

 Large, cephalon rather square, with rounded anterior ends; 



eyes large, reniform; ocelli on faint swellings between the com- 

 pound eyes ; abdomen increases slightly in width to third segment, 



Fig. 1708. Eurypierus lacustris, a nearly complete individual, but with only one ap- 

 pendage preserved, X %• (Pal. N. Y., III.) 



then tapers to very long telson; body covered with coarse, imbri- 

 cating, crescentric scales; length 20-30 cm. 



Pittsford shale (Lower Salina) of New York. 

 15. E. eriensis Whitfield. (Fig. 1707.) Siluric. 



Cephalothorax semioval, regularly rounded; eyes small, rather 

 close together; abdomen scarcely widening to the fourth somite, 

 after which it tapers rapidly; last three segments of nearly equal 

 width. 



Put-in-Bay dolomites (Lower Monroe) of Ohio, Canada, etc. 



