338 BULLETIN 97, UNITED STATES NATIONAL MUSEUM. 



Thus far I have considered the American and East- Atlantic form 

 the same as that from the Indo-Pacific region, but have now come to 

 the conchision that they are different. 



Diagnosis. — Tubercles of carapace flattened, depressed. No bristles 

 on inner surface of palm. Merus joints of legs not especially elon- 

 gated or narrowed. 



Description. — Carapace ovate, thin, disk-like, longer than wide, 

 covered with little short bristles, which, however, leave certain sym- 

 metrical raised linear patches bare; merus joints of legs clad in the 

 same way, and with two long bare stripes. 



Dorsal surface of carapace with a few low tubercles; one behind 

 the inner angle of the orbit has a sharp point anteriorly. 



Front, antennular and supra-orbital angles, and epistome all 

 acutely spinose. Front, between the antennules, narrow, contained 

 more than G.5 times in the fronto-orbital distance; just as wide as 

 long or very slightly wider than long, the length measured from 

 the hinder end to the sinus of the posterior tooth; armed with four 

 spines (two on each side), and a row of spinules, which are very in- 

 conspicuous, just within and parallel to each side-margin. Three 

 spines on inner margin of orbit; the middle of the upper border is 

 also more or less serrate. Ej'^es large and reniform. Antero-lateral 

 border of carapace armed with four acute spines; the first is at the 

 angle of the orbit; the other three are smaller and subequal to one 

 another. 



The chelipeds vary according to age and sex, but arm and wrist 

 are always armed with spines; palm nearly smooth and nude, oval 

 and somewhat compressed, very deep in the adult male; fingers 

 short, blunt and hollowed at tip. Proximal upper surface of palm 

 with a short, ill-defined furrow, not more than half as long as upper 

 margin, and filled with pubescence. No patch of hair on inner sur- 

 face of palm. Merus joints of legs not extraordinarily elongated 

 or narrowed. Anterior border of merus joints armed along its whole 

 length with large and even spines; posterior border ends in a spine; 

 on the merus of the first two legs there is a second row of spintiles 

 parallel with the anterior border; on the third merus this row is 

 indistinct; and on the fourth quite absent. 



Color. — Carapace usually variegated or mottled with brown, pink- 

 ish flesh-color and salmon; there is generally a median longitudinal 

 stripe of bright pale blue; the legs are banded witli reddish-brown 

 and light pink. Ventral side of body pale blue; of legs pale pink. 

 (Verrill.) 



Measurements. — Male (13828), total length of carapace 27.7, width 

 of same 20, fronto-orbital width 17.1 mm. 



Tlahitat. — Found on outlying rocks Avashed by the spray. Its body 

 and spiny legs look as if they had been ironed out. (Jarvis.) 



