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PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. XXXII. 



almost straight, slightl}^ convex, and armed with four or five spines 

 and a few short hairs; dact^yl as long as the palm and fitting it closely. 

 Second gnathopods with a carpus broader than in the first pair but 

 similarly armed; propodus not so l)road as the carpus, about twice as 

 long as broad and larger than in the first gnathopods; posterior mar- 

 gin almost straight; anterior margin slightly convex and usually fur- 

 nished with one or two fascicles of hairs; palm very oblique, slightly 

 concave at the center, armed with five or six spines at the tip of the 

 closed dactjd, and one or two spines and a few short hairs on the 

 margin; dactyl strongly curved, as long as the palm. 



Pig. 12. — Gamm.\rus cecus, male. Modesta Cave, near Canas, Cuba. 



Both margins of the coxal plates of the third, fourth, and fifth 

 peneopods are serrate and furnished with spines, those on the anterior 

 margin being smaller than those on the posterior. 



Postero-lateral angles of the third and fourth abdominal segments 

 are produced backward and end in a blunt tooth. The last two or 

 three abdominal segments are furnished dorsally with a few short 

 spines. 



The first uropods project slightly beyond the second pair. In both 

 pairs the rami are about equal in length and slightly longer than the 

 peduncle. The third uropods were broken off in the few specimens 

 which I had for examination. Telson cleft to the base, armed distally 

 with a few short spines. 



