94 U.S. NATIONAL MUSEUM BULLETIN 259 



posterior margin with 2 sets of setae; superior lateral setae few, 

 doubly inserted, inferior lateral setae singly inserted; dactyl claw 

 rather long. Gnathopod 2 : propod palmar margin slightly concave, 

 armed with a double row of 9 or 10 spine teeth; posterior angle with 

 1 large spine, 4 smaller spines and several setae on outside, 4 or 5 small 

 spines on inside; posterior margin with about 5 sets of setae; superior 

 lateral setae triply, doubly, and singly inserted, inferior lateral setae 

 mostly singly inserted; dactyl claw rather long. Coxal plates of 

 pereopods 2 and 3 about as broad as long, marginally with about 6 

 or 7 setae each. Coxal plate of pereopod 4 a little broader than long 

 with 6 or 7 marginal setae. Pereopod 7 about 50 percent as long as 

 body, a little longer than pereopod 6 and 40 to 45 percent longer than 

 pereopod 5. Bases of pereopods 5-7 corresponding closely to those 

 described for S. alabamensis and S. balconis, about as broad proximally 

 as distally and possessing broad distoposterior lobes. Dactyls of 

 pereopods 6 and 7 about 1/4 as long as corresponding propods; that 

 of pereopod 5 about 1/3 as long as corresponding propod. Two pairs 

 of unequally forked, bifurcate sternal gills present on pereonites 6 

 and 7; small coxal gills present on pereopod 7; median sternal and 

 pleanite sternal gills absent. 



Abdominal side plates: posterior margins convex, \vith 4 or 5 setae 

 each; posterior corners rounded; ventral margins of plates 2 and 3 

 with 4 or 5 spines. Pleopod 1, inner ramus about 30 percent longer 

 than peduncle. Uropod 1 : inner ramus a little longer than outer 

 ramus, about 60 percent as long as peduncle, armed with up to 10 

 spines; outer ramus with up to 11 or 12 spines; peduncle with about 

 10 spines. Uropod 2: outer ramus about 2/3 as long as inner ramus, 

 40 to 45 percent as long as peduncle, armed with 7 or 8 spines; inner 

 ramus with about 9 or 10 spines; peduncle with 5 spines. Uropod 3, 

 ramus about 1/3 as long as peduncle, armed apically with usually 2 

 spines. Telson about 30 percent longer than broad, gently tapering 

 to convex apex, which is armed with 9 or 10 unequal spines, the outer 

 spine on either side being strongly deflected laterally from the midline 

 and possessing 1 small, distal tine. 



Female. — Differing slightly from the male as follows: Antenna 1 

 between 40 and 45 percent as long as body, about 40 percent longer 

 than antenna 2. Antenna 2, flagellum with 11 segments. Gnatho- 

 pods with a few more spines on propod palms and posterior angles in 

 larger specimens. Pleopod 1, inner ramus up to 45 percent longer 

 than peduncle. Uropod 1, inner ramus only 50 percent longer than 

 peduncle which possesses about 15 spines. Uropod 2: outer ramus 

 only about 30 percent as long as peduncle; inner ramus armed wdth 

 up to 1 1 spines; peduncle with 8 spines. Uropod 3, ramus occasionally 



