ISOPODS OF NORTH AMERICA. 



165 



jointed; first two joints short and stout; second joint stout, decreasing 

 distal ly; third joint slender and tapering, set at an angle to second 

 joint and furnished at its tip with several setie, one of which is usually 

 longer and stouter than the others. Maxillipeds with rather slender 

 five-jointed palp, more slender in male, first joint shortest, second 

 joint longest, two to three times as long as first. 



"First pair of thoracic limbs with fifth joint set obliquely to the 

 plane of the preceding joints, very short, almost hidden on inner or 

 anterior face, but triangular and appearing to be deeply embedded in 



FIG. 147. NALICOBA RAPAX (AFTER MOORE), a, GENERAL FIGURE, b, SECOND MAXILLA, c, SECOND 



ANTENNA, d, FIRST MAXILLA. 6, SEVENTH LEG. /MANDIBLE, g, MAXILLIPED. /I, FIRST LEG (POS- 

 TERIOR), i, FOURTH LEG. j, FIRST LEG (ANTERIOR), k, FIRST LEG (INFERIOR). , PART OF TERMI- 

 NAL SEGMENT OF ABDOMEN WITH UROPODA. 



fourth joint when viewed externally; fourth joint with about four 

 stout spines on inferior edge, second limb with fifth joint longer and 

 with slight obliquity; third pair similar but longer. Pairs four to 

 seven more slender, with numerous spines, the third, fourth, fifth, and 

 sixth joints subequal. 



"Uropods stout, the peduncle prolonged at its inner angle into a 

 robust process. Inner ramus broad (about 1.5 times as long as broad), 

 extending beyond end of telson; outer ramus shorter and narrower, 

 extending barely beyond tip of telson; apex truncate or subbifid. 



