165 



First segment of pleon with a triangular spine, behind which a low 

 central carina is continued to the extremity of the sixth segment of 

 the pleon, rising into a spine on the posterior margin of the fifth and 

 sixth segments. 



Opthalmic peduncle shorter than the basal joint of antennulae, cor- 

 nea large, broader than the peduncle, its width about equal to the 

 length of the visible portion of the latter. 



Basal joint of antennular peduncle broad, armed with two sharp 

 lateral spines, one behind the other, in a line with the lateral spines of 

 the carapax ; flagella of antennulae scarcely as long as the two distal 

 joints of the peduncle, the joints much shorter than broad. 



Spine of antennal scale extending slightly beyond the antennular 

 peduncle, the squamose portion broad, not longer than the spinose 

 portion. 



Peduncle of antennae slightly shorter than that of anteunulae, its 

 terminal joint setose on its internal margin, flagellura much shorter 

 than the body, its articulations broader than long, especially the prox- 

 imal portion, where they are depressed and margined with seta inter- 

 nally and externally. 



Outer maxillepeds extending beyond antennal peduncle, the propo- 

 dus margined internally with long setae. 



Meros, carpus and propodus of first pair of legs equal in length, all 

 the joints of second pair longer, but the carpus longer than the raeros ; 

 in the third pair, which extends beyond the outer maxillipeds when 

 straightened, all the joints are longer than in the second pair, and 

 the slender carpus almost twice the length of the propodus. 



Propodi of three first pairs similar, that of the third pair somewhat 

 longest, fingers parallel, equal to the palmer portion in the first and 

 second pairs* but shorter in the third. 



Fifth pair longer than the fourth, dactyli laminate. 



A spine at the tip of the outer caudal appendage externally* 



Length of a large specimen, 3J" 



Length of carapax, 0-35" 



Length of outer antennae, 1'85" 



Dredged from a depth of 14 fathoms, in Bolinas Bay, Lower Cali- 

 fornia; also obtained in Angeles Bay, Gulf of California. (W. J. 

 Fisher.) 



Color after two weeks exposure to alcohol, bright red ; with a dark 

 red- brown ocellated spot on each side of the carapax. Antennae blu- 

 ish. 



A longer exposure to alcohol has bleached the body, but the anten- 

 nae still show traces of blue, and the spots on the carapax, though 

 obsolete in one specimen, remain dark and conspicuous in another. 



This form resembles S. carinata Dana (U. S. Ex. Exp. Crust., I, p. 

 602), but the rostrum is more prominent. 



