106 Bulletin Vanderbilt Marine Museum, Vol. VI 



ate, upward directed, triangulate, acuminate rostrum that extends 

 above the eyes semihood-like and reaches slightly beyond the dis- 

 tal corneal margin, or to the base of the second article of the an- 

 tennular peduncle. On either side of and immediately adjacent to 

 the rostrum, the frontal margin of the carapace is rather deeply 

 concavely excavate above the eye, the postorbital angle being 

 rounded and the lower frontal margin truncate and closely ap- 

 pressed with the anterolateral angle also closely appressed to the 

 body and rounded as in the genus Crangon. The posterior mar- 

 gin of the carapace is decidedly concavely excavate across the 

 median dorsal region, this excavation showing the only visible 

 portion of the first abdominal segment ; the rounded anterolateral 

 margins of the second abdominal segment overlap the postlateral 

 margin of the carapace. 



The abdominal segments are moderately compressed laterally, 

 glaucous, semitranslucent ; the first and second segments with 

 deep, widely convex lateral borders; the rather large clutch of 

 eggs being held beneath these two segments and anterior to the 

 second pair of pleopoda ; the third, fourth and fifth segments have 

 the lateral margins less produced, shallowly rounded. The pos- 

 terior third of the third segment and the entire fourth and fifth 

 segments are weakly carinate in the median dorsal line ; the fifth 

 segment is produced posteriorly in the median dorsal line into an 

 acute, subdistal spine, the apex of which scarcely exceeds the pos- 

 terior margin of this segment. The sixth segment is no longer 

 than the fifth and bears a small blunt tubercle proximally in the 

 median dorsal line but has no carina. The telson is 2.5 millimeters 

 long, or one and one-fourth times as long as the sixth segment, 

 not decidedly tapered for about five-sixths of its length, the dorso- 

 lateral borders, consisting of a pair of decided ridges, one on each 

 side, separated throughout their length by a pronounced median 

 longitudinal channel ; the true distal margin is narrow, each half 

 converging to form a small triangular apex. There are three pairs 

 of articulated spines on the dorsal surface of the telson, the first 

 pair being subproximal, the second pair about midway the length, 

 and the third pair subdistal, nearly marginal, one spine of each 

 pair being placed on each side on the longitudinal ridges. The 

 distal telsonic margin has a small pair of submedian, short 

 spinules ; outside of these there is the one pair of long, acuminate 

 spines, each of which is equal in length to the distance between 



