138 Bulletin, Vanderhilt Marine Museum, Vol. Ill 



straight forward, with the anterior half of the upper margin more 

 convex than the proximal, forming a crest, the entire dorsal margin 

 armed with a series of eight to ten teeth, the posterior two of which 

 are on the carapace posterior to the orbital angle; there is a strong 

 lateral carina on the rostrum; the lower margin is convex, widest 

 just in advance of the eye, armed with six or seven acute teeth with 

 a dense fringe of cilia interspersed between the teeth. The carapace 

 is short and robust, its length scarcely exceeding its height, with a 

 well developed postorbital spine, none at the antennal angle of the 

 margin, but one on the carapace subdistal to the margin, behind the 

 antenna. The rostral carina is continuous on the carapace for nearly 

 half its length. The abdomen is robust, the last four segments flexed 

 downward, nearly at a right angle to the remainder of the body. The 

 first, second and third segments have the epimeral plates much 

 developed, with rounded margins. On the fourth and fifth segments 

 the lateral margins are much less produced; the sixth segment is 

 only a little longer than the fifth; the telson is one and one-half 

 times as long as the sixth segment, tapering, with a submedian pair 

 of longitudinal carinae, from which there arise two pairs of articu- 

 lated spines; besides these, there is, at the apex of the telson, a pair 

 of long, articulated spines, placed one on each side of the apex and 

 extending beyond it. The caudal fan is well developed, margins 

 ciliated; both blades oval, the outer one wider than the inner and 

 with a subdistal spine on the outer lateral margin. 



The eye is terminal, placed on a well developed, articulated stalk; 

 the cornea bulbous, with a strong ocellus on the dorsal surface. 



The antennulae have the basal article flattened below the eye, the 

 outer lateral margin thickened in a ridge, which terminates distally 

 in a long, acute spine that reaches almost to the distal margin of the 

 second segment, which is small, cylindrical; the third article is sub- 

 equal to the second; the flagellum is triramose, the shortest branch 

 being about half an inch long, thick, setose ; the intermediate branch 

 quite twice the length of the short one, and the longest branch quite 

 four times the length of the shortest and very slender. 



The antennae have a stocky peduncular article, the upper and 

 lower outer dorsal angles toothed ; the second and third articles 

 stocky, short, the whip slender, about as long as the body of the 

 animal. The scaphocerite reaches as far forward as the rostrum and 

 has the distal margin evenly convex and ciliated, a subdistal tooth 



