G. M. Thomson. — Notes on New Zealand Crustacea. 207 



ISOPODA AbERRANTIA. 



Fam. TANAID^. 

 Body narrow and elongated. First pair of gnatliopoda (anterior feet) 

 large, and furnished with a didactyle hand ; second pair approximating to 

 the pereiopoda. Eggs borne in a sub-pectoral pouch beneath the five 

 central segments of the body. Abdomen terminated by two setaceous 

 articulated appendages. 



Genus Tanais, Audouin and M.-Edwards. 



Cephalon and first segment of pereion confluent. Antennse short, sub- 

 equal. First pair of gnatliopoda very large, didactyle ; second pair slender 

 and simple. Pleon five-jointed, fourth joint short, fifth terminated by a 

 pair oi singJe-hrancJied, filamentary uropoda. 



1. T. nov(€-zeaIandi(E, G. M. Thomson (Ann. & Mag. N.H., ser. V., 



vol. IV., p. 418). 



Fig. 3. 



Body broader than deep, with transverse fascicles of rough (furry) hairs, 

 on the three anterior segments of the pleon. Eye very small, black, and 

 circular, placed on a prominent lateral lobe of the anterior margin of the 

 head. Superior antenna three-jointed, setose at the extremity ; first joint 

 longer than the two succeeding. Inferior antennse rather shorter than 

 superior. First gnatliopoda very stout, the immobile finger of the hand 

 smooth on its inner margin, or only slightly denticulated. Second gnatho- 

 poda very slender. Posterior pleopoda bearing a smooth — not denticulated 

 — sickle-shaped finger, with a few long cilia at its base. Terminal uropoda 

 almost as long as antennse, five-jointed, and with numerous setse. Length 

 •18 inch. 



Hab. Dredged in Dunedin harbour, 4-5 fathoms. 



Genus Paratanais, Dana. 



Cephalon fused with first segment of pereion. Eyes shortly peduncu- 

 lated. Antennae without a flagellum, (with rudimentary flagella. Bell) ; 

 inferior pair more slender than the superior. Gnathopoda as in Tanais. 

 Pleon with six segments ; five anterior pairs of pleopoda, formed of ciliated 

 swimming-plates ; sixth segment terminated by a pair of two-branched sub- 

 sty liform uropoda. 

 1. P. tenuis, G. M. Thomson (Ann. & Mag. N.R, ser. V., vol. VI., p. 2.) 



Body slender. Head (when seen from above) narrowing anteriorly, 

 front margin nearly straight. Eyes triangular ; peduncles so short as to 

 be scarcely visible. Superior antennae stout ; inferior pair about two-thirds 

 as long as superior, and slender. First gnathopoda stout ; mobile finger 

 smooth on the inner margin ; immobile finger terminated by two or three 



