160 RECORDS OF THE AUSTRALIAN MUSEUM. 



The sixth segment has superiorly a faint longitudinal mesial 

 groove, and two pairs of submedian tubercles ; the anterior pair 

 are separated by the groove, the posterior pair are much wider 

 apart and nearer the hinder margin ; the latter bear about eight 

 tubercles, four on each side of a short central ridge. 



The uropods and telson have the basal third calcified. The 

 superior distal margin of the outer ramus has eight small denticles, 

 and that of the inner ramus two or three situated on the outer 

 fourth. 



The telson is marked by four smooth pit-like depressions, the 

 anterior pair are wide apart and seated on the base, the posterior 

 pair are large, submedian, and occupy the distal half of the calci- 

 fied part. The membraneous laminte of the uropods and telson 

 have numerous radiating ribs, which exhibit repeated dichotomous 

 branching ; the ribs on both surfaces of the telson and on the outer 

 halves of the rami are closely granulose. 



The pleopoda are biramous ; the first pair are wanting in both 

 male and female. The second pair in the former are foliaceous 

 and have the rami equal in length ; the outer one is broad at the 

 base, and the inner one rather narrow. In the succeeding pairs 

 the outer ramus is similar in .shape to that of the second, but the 

 rami decrease in size on each somite ; the inner ramus is 

 represented by a short obtuse conical stump. It is interest- 

 ing to note that the inner ramus of the fourth segment on 

 the left side — in the male example under notice — is consider- 

 ably developed, it is equal to the outer in length but is 

 very narrow and styliform ; a small stylamblys occurs at its 

 base. 



The second pair of pleopoda in the female are very large, and 

 consist of foliaceus plates with strongly ciliated margins. The 

 inner ramus is rather broader than the outer, and carries a single 

 stylamblys tipped with long sette, to which the ova are attached. 

 In the following pairs the lamina of the outer rami is much 

 smaller than those of the second ; the inner ramus is narrow, 

 elongate, and three-jointed ; a foliate plate arises from the outer 

 base of the second joint. The margins of the joints and lamina 

 are more or less fringed with long plumose hairs to which the 

 bundles of ova are cemented. 



Basal joint of first antenna tuberculate, twice as long as broad, 

 the inner distal angle terminating in a prominent denticle ; second 

 joint stout, smooth, compressed, nearly twice as long as the first, 

 and equal to the third ; fourth shorter than the latter, about twice 

 as long as the outer flagellum. 



Outer antenn;e a little shorter than the inner. The basal joint 

 is very large ; the inferior distal margin is denticulate, it carries 



