770 CRUSTACEA. 



Plate 51, fig. 4 a, animal, enlarged one and a half diameters; b, 

 front view of front ; c, leg of second pair ; d, leg of seventh pair ; g, 

 caudal stylet; e, epimeral of first segment; /, epimeral of seventh 

 segment. 



Nassau Bay, Fuegia. 



Length of body, fourteen lines ; breadth, four and one-half lines. 

 Colour, according to a sketch by Mr. J. P. Couthouy, bluish in the 

 three posterior segments of the thorax, with the middle of the back 

 bordering on a slate-green, and the lateral portions of the four anterior 

 segments of the thorax and the abdomen a rose-red. The antennea 

 of the second pair are of sufficient length to reach to second thoracic 

 segment; those of the first pair are half shorter; the latter meet at base 

 on the medial line, and the first joint is very broad, being a little trans- 

 verse and marginate below. The surface of the body is shining, and 

 the texture of the shell is hard. The three posterior segments of the 

 thorax are longer than the three next anterior, as in Nerocila. The 

 short spines on the under side of the six anterior legs are evidently to 

 aid in crawling, while the claw is used for prehension ; the eight pos- 

 terior legs are cylindrical, with a few spinules at apex of joints, and on 

 their under surface. The abdomen and stylets are short ciliate. 



The epimerals have two oblique (nearly longitudinal) lines on each. 

 The posterior is nearly an oblique parallelogram in form, the lower 

 posterior angle being considerably prolonged and subacute. 



Subfamily CIKOLANINiE. 

 Genus CIROLANA, Leach. 



The similarity in general character between the following two 

 species, and the partly concealed first abdominal segment of the first 

 while the same is wholly concealed in the second, seem to show that 

 the distinction between Cirolana and Eurydice is generically of small 

 importance. 



