S rri"*. KKI'OKT OF llNXiKKSS. C. K. HHIX'H >:!:. 



Tki.sox short and bro:ul, tint and quadrani^ular on the 

 ventral side : trianirnlar and carinated on the dorsal side, 

 and produced info a long, slender spine, having a length 

 alxuit equal to twice that of the posterior segment of the 

 alxloMien. To the ventral side of the caudal plate are ar- 

 ticulated two movable spines, about equal in length to the 

 spin! form extension of the telson. These spines are grooved 

 ak)ng their lateral margins, and marked by a carina on their 

 dorsal face. 



Test thin, somewhat thickened on the margins and dorsal 

 line of the carapace, and at the articulations of the abdomi- 

 nal segments ; ornamented over the entire surface of the 

 carapace, mandibles, abdomen, and tail with minute gran- 

 ules or pustules, Avliich give a punctate appearance to the 

 whole. 



The specimen represented in Fig. 13 of Plate I has a 

 length, exclusive of the tail spines, of 57 m m. The cara- 

 pace measures 30 m m. in length, 20 m m. in breadth, and 

 18 m m. along the hinge- line. The segments of the abdo- 

 men, beginning with the anterior one, measure respectively 

 3.5, 3.7. 4, 4, 5, and 8.5 m m. in length, — showing that the 

 posterior segment is more than twice the length of any of 

 the first four segments. The three posterior ones, com- 

 mencing with the distal segment, have diameters of 5.5, 7, 

 and 8 mm. respectively. The left valve of this species 

 figured in the 16th Rept. N. Y. State Cab. Nat. Hist, has a 

 greatest length of 55 m m., with a breadth of 37 m m. 

 The three abdominal segments figured in the same publica- 

 tion also belonged to a much larger individual than any 

 noted in the present description. 



This species differs from £J. sublenis, Whitfield, (Am. 

 Jour. Sci., Vol. XIX, p. 36,) in the more numerous nodes 

 and tubercles of the carapace, the curvature and direction 

 of the ridge along the thoracic portion, and in its more elon- 

 gated abdominal segments. The same characters serve to 

 distinguish it from E. pustulosa, Whitfield, (loc. cit.,) 

 with the addition of a marked difference in the surface or- 

 namentation, which in that sj^ecies is distinctly pustulose. 

 It is readily distinguished from E. socialis, in its larger 



