200 Transactions. — Zoology, 



nearly smooth. Head emarginate anteriorly, the middle of 

 the notch straight ; the antero-lateral angles rather prominent 

 and rounded. First thoracic segment with the antero-lateral 

 lobes rather broad, and not reaching nearly to the eyes. 

 Postabdomen as long as the four or five posterior thoracic 

 segments ; terminal segment with two small sutures on each 

 side near the base (indicative of coalescent segments), and 

 with svibparallel sides, distal end usually broadly triangulate, 

 and apex subacute. Eyes of moderate size. Antennules 

 scarcely reaching to the base of the antepenultim'ate joint of 

 the peduncle of the antennae, with their basal joints consider- 

 ably dilated. Antennee with the joints of the peduncle short, 

 the last two subequal, and each but little longer than the 

 antepenultimate joint ; flagellum 16-21-jointed, and longer 

 than the peduncle. The epimera are narrow, and in the second, 

 third, and fourth thoracic segments scarcely occupy more than 

 half of the lateral margins ; in the fifth segment they reach 

 nearly, and in the sixth and seventh segments quite, to the 

 postero-lateral angles, and in these segments are of a more or 

 less triangulate shape. The legs are very slender. The ter- 

 minal plates of the opercular valves are three-sided, with their 

 outer margins curving to the distal extremity, which is sub- 

 acute or blunt. Length of the largest male, about Ifjin. 

 (48mm.) ; breadth, nearly x\in. (10mm.) ; but most of the 

 specimens are much smaller." — [Miers.] 



In Miers's " Eevision of the Idoteid en," this species is re- 

 corded from various parts of Australia, but it has not hitherto 

 been recorded from New Zealand. I first recognised it from a 

 specimen sent me from Lyttelton Harbour by Mr. E. M. Laing; 

 there is a specimen in the Dunedin University Museum from 

 Cape Campbell ; and in Mr. Thomson's collection there were 

 two specimens from Waipapa Point, collected by Mr. J. F. 

 Erecson, and a small specimen from Moeraki, collected by 

 Professor Parker. On several occasions I have picked up 

 fragments of this species which had been w^ashed up on the 

 Ocean Beach, Dunedin. These fragments consisted of the 

 skeleton of the postabdomen and one or two posterior seg- 

 ments of the thorax. Curiously enough, I could find no trace 

 of the head and anterior segments of the thorax, though at the 

 same time and at the same place I gathered fragments con- 

 sisting of the head and anterior segments of the thorax of 

 Pseudcega yunctata, Thomson, but could not find any trace of 

 the hinder parts of the body of this species. My fragments of 

 Idotea peronii when gathered were light reddish-pink in 

 colour, but whether this had been the colour of the animals 

 when alive I cannot say ; the other specimens, from Lyttelton, 

 &c., are in spirit greyish, sometimes closely covered with 

 small dark spots. 



