164 BULLETIN 54, UNITED STATES NATIONAL MUSEUM. 



NALICORA RAPAX Moore. 



Nalicora rapax MOORE, Bull. U. S. Fish Commission, XX, Pt. 2, 1902, pp. 169-170, 

 pi. ix, figs. 11-22. 



Localities. Mayaguez Harbor, Porto Rico; Gulf of Mexico; lati- 

 tude 29 11' 30" north, longitude 85 29' west; latitude 28 46' north, 

 longitude 84 49' west; latitude 29 16' 30" north, longitude 85 82' 

 west; between delta of the Mississippi and Cedar Keys, Florida. 

 Depth. 25-75 fathoms. 



"Body convex, about 2.3 times as long as broad, first thoracic seg- 

 ment longest, next five about two-thirds as long and subequal, last 

 shorter; posterior four thoracic segments with a row of setae across 

 middle and another on posterior margin, hairiness increasing posteri- 

 orly, occasionally a few setae on second and third. Fifth segment 

 broadest. 



"Pleon and telson about two-fifths as long as rest of body. Pleon 



of four visible segments, first short and nar- 

 rower than second and third and hidden at 

 side by seventh thoracic; second somewhat 

 produced at posterior lateral angle; third 

 segment strongly produced, angle reaching 

 to beyond base of uropods. 



"Epimera of all the thoracic segments 

 except the first distinct, of second and 

 third not produced posteriorly, the follow- 

 ing ones successively more produced, the 

 last two terminating in strong angles. 

 LOBE OF FIRST MAXILLA, x 5if. " First antennae about as long as pedun- 

 cle of second antennae; peduncle of two 



equal joints, flagellum slightly longer than peduncle, about eight or 

 nine jointed; distal ends of segments furnished with a few short hairs; 

 second antennas reaching to end of second thoracic segment; peduncle 

 five-jointed, fifth joint longest, slightly exceeding the fourth, which is 

 as long as first three joints together. 



"Mandible weak, with bifid cutting edge and three-jointed palp. 

 First maxilla large, robust; plate of first joint expanded at distal end 

 into a somewhat quadrate curved face closely beset with papillae and 

 looking like a triturating plate; third joint very stout, strongly curved 

 with a very strong terminal spine continuous in contour with the rest 

 of the joint; at base of curved portion, on inner side, a stout knob- 

 like protuberance. The first maxilla is the largest and most conspicu- 

 ous of the mouth parts, overlapping and hiding the mandible, and in 

 the male reaching to the base of the antennae. In the female the ter- 

 minal spine is straighter, not so continuous with the rest of the plate, 

 and points inward and somewhat backward. Second maxilla four- 



