20 A. 0. WALKER. 



There are other slight differences, such as the greater relative width of the first 

 joint of the upper antennae ; more slender gnathopods ; the third joints of the fourth 

 and fifth peraeopods more acutely produced, etc. It is possible that it might prove to 

 be a distinct species if the males were known. 



Pboboliella. 

 ProloMla, A. 0. Walker, Ann. and Mag. Nat. Hist. XVIII. (1906), p. 13. 



Mandibles with a two-jointed palp. 



First maxillse with a two-jointed palp. 



Maxillipeds with the inner plates divided to the base ; the outer more or less 

 developed. 



Second perseopods not stronger than the first ; third perseopods with a narrow first 

 joint ; fourth audi fifth with an expanded first joint. 



P. TYPICA. (PI. 6, fig. 10.) 



P. tyfica, A. 0. Walker, Ann. and Mag. Nat. Hist. XVIII. (1906) p. 14. 



W.Q., Hut Point, 11 Nov., 1902, one; 13 Oct., 1902, one; 18 Feb., 1904, one. 

 All females. 



Female — 



Body tumid. Posterior angle of the third pleon segment produced and rounded. 



Eye small, round, colourless in spirit. 



Upper antennse without an appendage, reaching to the middle of the flagellum of 

 the lower ; the third joint half as long as the second ; flagellum seven -jointed, as long 

 as the two last joints of the peduncle. 



Mandibles bent downwards from the base of the palp and narrowed towards the 

 coarsely toothed cutting edge ; the palp more than half the length of the mandible ; 

 the first joint less than one-fourth as long as the second. 



Maxillipeds : Inner plates divided ; outer distinct, though narrow ; first and 

 second joints of the palp subequal, the third longer. 



First gnathopods : Wrist shorter and narrower than the hand ; palm very oblique, 

 about as long as the rest of the hind margin, spinulose, and defined by two or three 

 long spines. 



Second gnathopods : Side-plates oblong, convex in front, straight behind, the angles 

 rounded with a small tooth. First joint strong, as long and more than half as wide as 

 the hand, fringed with setae before and behind ; third joint produced behind to a very 

 acute point, which extends a little beyond the carpal process. Hand subelliptical, 

 the palm longer than the rest of the hind margin, convex, spinulose, and defined by a 

 strong tooth, beyond which is a smaller tooth and a group of spines. 



First perseopods: Side-plates oblong, angles rounded, margins parallel; first 



