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segments of mesosome to simple, triangularly-pointed projections successively 

 increasing in size, on each of the segments of metasome to 2 successive points, the 

 posterior of which is the larger, and somewhat upturned on the last segment. 

 Segments of urosome likewise produced dorsally, but in a somewhat different 

 manner in the two sexes; 1st segment in female with 2 successive projections, 

 in male with only a single one; dorsal projection of 2nd segment in male 

 much larger than in female, and strongly deflexed. Metasome very powerfully 

 developed, being, in female, fully as long as the mesosome, in male, consider- 

 ably longer. Cephalon about the length of the first 4 segments of mesosome 

 combined, its upper contour forming a perfectly even curve until the tip of the 

 rostrum, the latter nearly perpendicularly deflexed, and reaching a little beyond 

 the basal joint of the superior antennae, lateral parts separated from the rostrum 

 by a deep and narrow sinus. The 3 anterior pairs of coxal plates not fully as 

 deep as the corresponding segments, and narrowly quadrangular in form, with 

 the tip transversely truncated; 4th pair somewhat less deep, and trian- 

 gularly pointed at the tip, posterior edge very slightly emarginated in its 

 upper part; the 2 succeeding pairs but little broader than they are deep, 

 posterior lobe somewhat deflexed, and narrowly rounded at the tip. First 

 pair of epimeral plates of metasome evenly rounded, 2nd pair considerably 

 deeper, and produced at the lateral corners to a short recurved point, last 

 pair produced to a much coarser spiniform projection defined above by a deep 

 sinus, posterior edge strongly curved, and divided into 5 coarse, recurved den- 

 ticles. Eyes wholly absent, not even the slightest trace of any replacing 

 pigment being observed in the living animal. Superior antennae in female 

 scarcely exceeding 1 U of the length of the body, 1st joint of the peduncle 

 but little longer than the 2nd, which about equals in length the 3rd, flagellum 

 not attaining the length of the peduncle, and composed of 9 articulations only, 

 accessory appendage rather small, biarticulate. Same antennas in male much more 

 fully developed, having the 1st joint of the flagellum very large, and densely 

 clothed with long and delicate sensory bristles, accessory appendage likewise 

 much larger than in female. Inferior antennas in the latter scarcely longer 

 than the superior, last joint of the peduncle a little shorter than the penulti- 

 mate one, flagellum about half the length of the peduncle; those of male 

 much more elongated, though not attaining the length of the body. Grnatho- 

 poda very small, exactly alike, and setous at the edges, carpus rather elong- 

 ated, propodos scarcely half its length, and oblong oval in form, with the 

 inferior edge forming, above the middle, an obtuse angle, below which occur 

 2 successive simple spinules, dactylus rather short and distinctly biarticulate. 

 The 3 posterior pairs of pereiopoda much stronger than the 2 anterior, and 

 rapidly increasing in length, basal joint regularly oval and distinctly serrated 



