1358 CRUSTACEA. 



The cephalothorax is rather longer than broad, and slightly broadest 

 posteriorly. The first abdominal segment is about half the breadth of 

 the carapax. In the female, it has parallel sides along the posterior 

 half, but narrows anteriorly j it is sometimes a little longer than the 

 carapax. The following portion of the abdomen is longer than broad, 

 and rectangular in form, the stylets completing the posterior angles of 

 the rectangle. These stylets are furnished with three plumose setae, 

 as long as this smaller part of the abdomen. The external ovarian 

 tubes were about as long as the body, and contained each about one 

 hundred eggs. The male abdomen was imperfectly hexagonal, a 

 little oblong, the greatest breadth being near centre. The caudal sty- 

 lets scarcely project beyond the anus. 



Posterior antennae in female without a corneous spine exterior to 

 base ; in male, having two short hooks at apex. Spine of maxillae a 

 little curved, acute, about as long as buccal trunk. Second pair of 

 feet in female rather slender, with the finger about half the preceding 

 part in length and diameter, and having a small claw at apex. Same 

 in male very large, with the finger slender, subulate, with a stout seta 

 on the inside of the finger ; hand nearly half its length in breadth, 

 inner side nearly straight, without an immoveable finger. 



This species is near the G. pectoralis, but has the second cephalo- 

 thoracic segment longer, the female abdomen much longer, and the 

 second pair of feet in the male stouter, with a seta on the inside of 

 the finger; and the ventral furcula has the prongs divergent. 



Genus CALISTES, Dana. 



Caligo similis. Cephalothorax 2-articulatus, discis suctoriis nullis; seg- 

 rnento postico non alato. Pedes postici biramei, subnatatorii, setis 

 plumosis instructi. 



Near Caligus. Cephalothorax two-jointed, without disks for attach- 

 ment, posterior segment not alate. Posterior feet two-branched, 

 subnatatory, being furnished with plumose setae. 



Like the Caligi, the Calistes have the maxillae a little remote from 

 the buccal trunk, and aculeate backward ; there is but one joint to 

 the thorax posterior to the carapax, and the third pair of natatories 



