32 Addison E. Verrill, 



The marine genera included in this family differ from the fresh- 

 water genera of crawfishes (Astacidae) chiefly in the number and 

 arrangement of the branchial plumes. The latter, however, differ 

 considerably among themselves in that respect. 



Nephopsis Wood Mason, 1873. 



Form of body similar to that of Homarus, but more slender. 

 Chelae of first pair of legs moderately large and equal, or nearly 

 so, not carinated. Antennas with a long flagellum; no antennal 

 scale. Eye-stalks and eyes small ; rostrum long, with carinate and 

 dentate margins. Second and third pairs of legs much more 

 slender than first, and with small simple chelae. Telson with two 

 ribs or ridges ending in two terminal spines ; uropods large, ribbed. 

 Branchiae nineteen on each side, arranged like the posterior nine- 

 teen pairs of Homarus. No branchiae on the second maxillipeds. 

 Inhabitants of deep water. 



Nephropsis rosea Bate. 



Ncphropsls rosea Bate, Voy. of the Challenger, Macrura, vol. xxiv, p. 

 178, fig. 39, pi. xxiii, figs, i, 2, 1 i ; pi. xxiv, fig. I, b z, 1888. Faxon, 

 op. cit., p. 157, 1896. 



PLATE IX, FIGURES 3, 3A, 4 40. 



This is a very slender species. The epimeral processes of the 

 abdominal segments are very acute-angular ; those of the first two 

 segments are bidentate, as seen from below. The rostrum is long, 

 acute, carinate; with raised margins, strongly contracted proxi- 

 mally; at about the distal third there is a sharp spine on each 

 margin, at the wide base there is another pair of spines ; a short 

 distance back of these on the carapace and joined to them by a 

 slight carina there is a third pair of smaller spines ; anterior margin 

 of the carapace has a pair of strong antennal spines. 



Antennular peduncle is slender with the third article much the 

 longest; its outer flagellum is thickened distally; inner one is 

 about the same length, but much more slender. Antennal peduncle 

 is shorter and stouter. Larger chelipeds elongated ; chela simple, 

 not much smaller ; palm longer than fingers ; carpus has a terminal 

 and a subterminal spine; merus has a distal spine on the outer 

 side. 



