Chilton. — Additions to the New Zealand Crustacea. 173 



two following, and having the hand stout and ovate, and the finger long 

 and curved ; the second and third pairs similar in shape and equal in size ; 

 the four posterior pairs are all nearly equal to one another, and are non- 

 chelate. Fu'st five abdominal segments confluent ; the last segment has 

 its posterior edge notched at the centre. Its appendages are broad, oper- 

 culiform, and biramous, the inner branch formed of a single joint, broad 

 and concave, enclosing the other branch, which has two broad joints, the 

 basal one being much longer than the terminal joint. The terminal segment 

 (telson) squamiform, rectangular, with the posterior angles rounded. The 

 posterior edges of the telson and of the appendages of the last abdominal 

 segment are fringed with numerous long setae. Length, -3 in. 



Hab. Among seaweed in rock-pools, Lyttelton Harbour. 



This species differs from Anthura in that the first five (instead of four) 

 abdominal segments are confluent and that the inner antenna has a distinct 

 flagellum, but as I have only a single specimen I have not made a new 

 genus for it. 



AMPHIPODA. 

 Microdentopus maculatus, G. M. Thomson (Ann. & Mag. N.H., ser. v., 



vol. iv., p. 331). 



This species was described by Mr. Thomson, from a single specimen, a 

 female. It appears to be moderately common amongst seaweed in the 

 rock-pools at Lyttelton. Amongst some specimens answering very well to 

 his description I took one which also agreed with that description in every 

 particular except as regards the gnathopoda. These (plate VIII. , fig. 3) are 

 very peculiar, the meros is produced inferiorly into a long acute spine 

 reaching slightly beyond the extremity of the succeeding joint, the earpus ; 

 this spine bears a small tuft of set» about one-third of its length from its 

 extremity. The carpus is large, and is rather more than twice as long as 

 broad. The propodos is much smaller; its inner edge is fiinged with 

 numerous setae. The last joint forms a strong finger slightly curved at the 

 end, its inner edge is smooth ; numerous long setae arise at its base. The 

 second pair of gnathopoda are of more normal shape, the meros not being 

 produced into a spine. 



The first pair of gnathopoda closely resemble those of Aora gracilis and 

 Aora typica,'^- though shghtly different from both of them. Mr. Thomson 

 has taken Aora tyjnca in Dunedin Harbour, and he speaksf of its resem- 

 blance to Microdentopus maculatus, and hints that they may possibly be 

 male and female of the same species. The animal I have, though distinct 



* " Brit. Mus. Cat. Ampbip. Crust.," pp. 160-2, pi. xxix., figs. 7 and 8. 

 t " Trans. N.Z. Inst.," vol. xiii., p. 218. 



