10 g4 CRUSTACEA. 



Very slender. Front much elongate, subacute. Cephalothorax rounded 

 behind, five-jointed, last segment nearly obsolete, second, third, and 

 fourth acute on either side behind. Anterior antennas one and a half 

 times as long as body, very nearly straight, hardly arcuate, tips an- 

 terior to front, setse mostly very short, one on third joint rather long, 

 apical and penult setae short, posterior antepenult somewhat long. 

 Abdomen short. Caudal stylets oblong, setae much spreading. 



Plate 76, fig. 2 a, animal, enlarged ; a', profile view of front ; I, 

 maxilla; c, a natatory leg; d, form of heart. 



Collected four or five individuals in the Atlantic, November 3, 1838, 

 latitude 1° north, longitude 18° west. 



Length, one-eighth of an inch. Colour, reddish in spots about the 

 articulations of the cephalothorax. This species is very near the 

 preceding, but has the antennae straight, and the abdomen four-jointed, 

 besides other points of difference. The four posterior segments of the 

 cephalothorax are scarcely one-third the whole length. The forks of 

 the beak are seen in an upper view, as in the figure. The abdomen is 

 four-jointed; first segment about as long as broad, the next two together 

 about the same length. The stylets are much more oblong than in 

 the rostrifrons. The caudal setae were partly mutilated ; the exterior 

 one arises, as in the rostrifrons, on the outer side of the stylet near 

 its base, the next, near its middle ; neither of these two are quite as 

 long as abdomen. There are four pairs of natatories, besides a pair 

 of small feet. 



This species approaches the Pontellae, but appears to be nearer Cala- 

 nus. The maxillipeds are large, nearly as in Pontella, but the following 

 organs, the first pair of feet, have lateral motion, and are moderately 

 lon^ 



*o* 



Genus EUCH^TA, PMUppi. 



The species of this genus collected by the author have the front in 

 a vertical view pointed, and acute or nearly so ; while in a lateral 

 view it is transversely notched, so as to be two-toothed. The cephalic 

 segment, as in the Calani, is never distinct from the following part ot 



