456 



bulletin: museum of comparative zoology. 



narrowing toward tip, two longitudinal grooves above, a small tooth 

 at end of outer margin which overreaches blade of scale; flagellum 

 more than twice as long as body. 



Mandible with a stout molar process and a 3-jointed palp ; the cor- 

 neous extremity of the molar process has a crenulated edge on one side; 

 the first and second segments of palp are of subequal length, the third 

 segment is about twice as long as the second, and has a fringe of long 

 bristles attached at and near the tip. 



The outer maxillipeds are stoutish and surpass the antennal scale 

 by J the length of the terminal segment; this segment is subsquamose, 

 being covered with deep pits from which arise fine setae. 



The first pair of pereiopods are shorter than the maxillipeds and 

 reach beyond their penultimate segment only by the length of the 

 fingers; the carpus widens considerably from the proximal to the 

 distal end; propodus nearly as long as carpus; palm swollen; fingers 

 § as long as palm, meeting throughout, tips corneous. 



Second pair of pereiopods filiform, very long, reaching beyond the 

 antennal scale by the length of the propodus and carpus and nearly 

 half the length of the merus ; the carpal segments vary from 26 to 32 ; 

 the merus also is faintly subdivided into segments varying from 12 

 to 17. 



Third, fourth, and fifth pairs of feet filiform, similar, the merus of 

 the third pair reaching a little past the middle of the scale, of the 

 fifth pair to the base of the scale; the third and fourth pairs are 

 similar in length, the propodus of the fifth pair is greatly elongated, 

 being 1| times as long as that of the fourth pair; dactyli short and 

 stout, tipped with a corneous spine which is nearly half as long as 

 the remainder of the segment; 2 more slender corneous spines on the 

 lower margin. 



The abdomen in its highest part is only about § the height of the 

 carapace; postero-lateral angles of third and fourth segments rounded, 

 of fifth and sixth segments armed with a short spine; length of telson 

 l\ times the sixth segment; the distance between the 2 pairs of dorsal 

 spinules is equal to the distance between the posterior pair and the 

 extremity; the terminal spines consist of a pair situated at the outer 

 angles, and longer than the posterior width of the segment, a pair of 

 short ones originating above and overlapping the long pair, and a 

 submedian pair of intermediate length originating at a lower level 

 than the others. The inner branch of the swimming fan is narrow- 

 oval, and reaches just to the end of the telson, exclusive of spines; 

 the outer branch is much larger, reaches nearly to the end of the 



