202 Bvlletin Vanderbilt Marine Mtiseum, Vol. VI 



they arise near the distal end on the outer side of carinae pair 

 III and extend obliquely almost to the distal posterior tooth of 

 pair V. The lateral carinae pair V arise each at the apex of the 

 postorbital tooth and curve back inward on the carapace, termi- 

 nating just anterior to the short spine that tips the apex of the 

 remainder of the second portion of this carina; the spine men- 

 tioned is approximately opposite the second spine of the median 

 dorsal carina. Lateral carinae pair V run obliquely outward 

 almost to the posterior margin of the carapace. The outermost 

 pair of lateral carinae are also long, beginning at the branchio- 

 stegal angle and extending posteriorly almost to the hinder margin 

 of the carapace ; about one-fourth of their length from the frontal 

 margin, these carinae each bear one acute spine, which is approxi- 

 mately in line with the spine of lateral carinae pair V. 



The median carina bears three spines, one distal, just posterior 

 to the base of the rostrum and continued back as a short carina 

 that ends just anterior to the second spine, which latter is ap- 

 proximately in line with the anterior spines of the lateral carinae 

 pairs V and VI ; the third spine of the median carina is very pos- 

 terior in position, being a short distance from the hind margin 

 and also accentuated on either side by a faint depression. 



The abdomen has the third and fourth segments carinate in 

 the median dorsal line, while on the fifth segment there is a dou- 

 ble carinae, V-shaped, bifurcating posteriorly, while on the sixth 

 segment there is a double longitudinal parallel carinae. The sixth 

 segment is one and a half times as long as the fifth segment, and 

 the telson is not quite one and a half times as long as the sixth seg- 

 ment, with a median longitudinal depression, bordered on either 

 side by paired carinae, which converge distally and bear two pairs 

 of articulated spines on the distal half. The distal telsonic margin 

 bears a submedian pair of acute, long spines, which are approxi- 

 mately one-fourth of the total length of the telson, and outside of 

 these there is a pair of small articulated spines, one on either side 

 of the long spines and situated at the distal angle of the telson. 

 The uropoda have the blades slender, elongate-oval, setae-fringed 

 distally. 



The eyes have the cornea rather large, nearly spherical, well 

 hooded by the carapace. 



The antennulae afford no specific characters. 



The antennae have the scaphocerite armed, with an acuminate 



