238 CRUSTACEA OF THE UNITED STATES. [Ma^ 



sixth abdominal segments, and the rostrum, are brown 

 above. 



Gmus CALLIANASSA. 



Four anterior feet didactylc; anterior pair largest, Very 

 unequal; second pair much smaller; third pair submono^ 

 dactyle; fourth -awd fifth pairs spurious, obsoletely didac* 

 tyle; c^if^wn^ inserted in nearly the same horizontal Xm^^in- 

 termediate ones with double seta and elongated peduncle 

 of which the terminal joint is much longest, exterior ones 

 without lamcllse; exterior caudal lamella simple. 



C. ^ major. Thorax one fourth the length of the body, 

 somewhat membranous, with an oval coriaceous plate 

 above, which before forms a rostrum of a very small pro- 

 jecting acute angle; eyes very small, placed on the upper 

 side of their peduncles, which are cylindrical, approxi- 

 mate at base, incumbent on and as long as the first very 

 short joint of the interior antennae, obtuse, and originat- 

 ing under the anterior margin of the thoracic plate; ex- 

 terior antenna longer than the thorax, two terminal joints 

 of the peduncle equal, seta more than thrice the length 

 of the peduncle; interiores more than twice the length of 

 the others, more robust, deeply ciliated beneath; external 

 pedipalpi with the second joint much largest, compressed, 

 oval, third joint not so large as the fourth, which is semi- 

 oval, terminal joint or nail closing on the edge of the 

 preceding joint; feet^ with the exception of the two last 

 ones, compressed; anterior larger foot placed indifferently 

 on the right or left, and is the only part that is of a com- 

 pact crusiaceous consistence, third joint sublinear, gra- 

 nulated, compressed within, convex on the exterior side, 



