628 CRUSTACEA. 



gulis anticis rotundatis et non acutis. Segmentum abdominis posticum 

 latere tridentatum. 



Near palliatus in general form of carapax and caudal Segment. Cara- 

 pax prolonged to penult segment of abdomen, not broader behind, 

 posterior angles long and acutely produced, hinder margin straight 

 and transverse, and armed at middle with an acute spinule ; lower 

 margin unarmed at middle; anterior angles rounded and not acute. 

 Caudal segment with three teeth on either side. 



Plate 41, fig. 7 a, animal, enlarged, dorsal view (young and but 

 partly matured) ; b, first pair of antenna, immature; c, second pair, 

 ditto ; d, one of the three posterior pairs of legs. 



South Atlantic, latitude 25° south, longitude 44° west. Collected, 

 January 10, 1839. 



Length, one-tenth of an inch. Colourless. The specimen is a 

 young, immature individual, and it is uncertain, therefore, how far 

 the existing characters are those of the mature animal. In the three 

 teeth on the sides of the caudal segment, the spinule of the posterior 

 margin of the back, and other characters, it differs from the palliatus. 

 The absence of a medio-lateral spine distinguishes it from the Guerinii 

 and Edwardsii. The beak is long and straight. The carapax is 

 slightly convex on the back, but bends down either side, and has 

 nearly the same form as in the palliatus. Its posterior margin passes 

 over the fifth abdominal segment, and the prolonged angles behind 

 reach nearly to middle of caudal segment ; but the segments of the 

 abdomen are but partly developed, and its appendages below are 

 wanting, excepting a rudimentary fifth pair, whence we may infer 

 that in the adult, the abdomen may extend farther behind the cara- 

 pax. The caudal segment is widest posterior to middle, and the 

 apical margin (which is transverse and spinulous) is much longer than 

 the basal. The anterior thoracic legs are not developed. There are 

 five successive pairs of legs, nearly similar in form, the last three pairs 

 of which are quite similar, consisting of a two-jointed base with a 

 furcate termination, the branches equal, one-jointed, setose. The 

 pair preceding these has one branch much the larger, though scarcelv 

 longer. 



