38o STALK-EYED CRUSTACEA 



Synopsis of the Species. 



A. The rasp on the penultimate joint of the fourth 

 pair of legs is composed of a single row of scales. — {S. 

 arcuatus?) 



B. The rasp of the penultimate joint of the fourth pair 

 of legs is composed of two rows of scales. — (.S. pictits.') 



C. The rasp on the penultimate joint of the fourth 

 pair of legs is composed of four rows of scales. — {S. 

 pilimaftus.) 



I. Sympagurus arcuatus. 



Sy)upagnnis arcuatus . A. Milne Edwards and Bouvier. 



The carapace is feebly calcified, almost smooth, and 

 naked. Rostrum almost wanting. Latere - frontal teeth 

 scarcely indicated. Ophthalmic scales narrow and 

 acuminate in front. Eye-stalks have dilated extremities, 

 compressed and hairy above. They scarcely exceed the 

 end of the acicle, reaching the extremity of the peduncles 

 of the external antennae, but not the extremity of the 

 penultimate joint of the peduncles of the internal antennae. 

 The internal antennse have many hairs on the last 

 peduncular joint ; their superior terminal flagellum is long, 

 thin, and exceeds the inferior. The basal joint of the 

 external antennae is visible from above; the flagellum is 

 long and naked ; the acicle has a row of sharp teeth upon 

 its internal border. 



The legs of the first pair are very unlike, the right is 

 longer and stronger; the hand is short, high, and slightly 

 hairy. 



The fingers move in an oblique plane. The fourth 

 pair of legs has a rasp composed of a single row of scales ; 

 the last pair is subchelate. 



Range. — St. Lucia, Dominica, Martinique. 



