108 Transactions.— Zoology. 
Hab. Common on seaweed along the shores of Otago Harbour, and in 
rock pools, and dredged in the harbour in six fathoms; also collected by 
Mr. C. Chilton on seaweeds in Lyttelton Harbour. 
2. Porcellidium interruptum, n. sp. Pl. XI., fig. 15. 
Body very broadly oval, width nearly equal to three-fourths of the 
length ; first segment about half as long as body; last thoracic segment 
produced behind into long pointed lamelle, which nearly meet posteriorly 
in the median line behind the caudal segments, the outer margin of each is 
finely ciliated and produced about the middle into a short spine. Inner 
branch of the first feet triangular, very broad at the base; outer branch 
nearly as long as inner. The second pair of feet have the outer branch 
short, hardly exceeding in length the first joint of the inner branch. Fifth 
feet form two somewhat curved lamelle, the inner of which almost extends 
to the extremity of the caudal segments: these last are rather longer than 
broad, their sides are nearly parallel, and their posterior margins fringed 
with a few short teeth. Length, zs of an inch. 
Hab. "Two specimens (both females) taken by the dredge in Dunedin 
Harbour. 
This is a very remarkable form and quite different from any hitherto 
described. 
Sub-fam. Ipvixx. 
Genus Idya, Philippi. 
Cephalothorax broad and somewhat depressed ; abdomen narrow, 5- 
jointed. Head coalescent with first thoracic segment. Anterior antenne 
T- or 8-jointed, elongated ; posterior 9-jointed, with a large 4-jointed . 
secondary branch. Mandible long and strongly toothed ; palp 2-branched, 
basal joint short, branches 1-jointed, long and slender, setiferous at the 
apices. Maxilla armed with several slender terminal teeth; palp well de- 
veloped. First and second foot-jaws nearly alike, hooked; first pair 2-, 
second 8-jointed. Inner branch of the first pair of feet 2-jointed, clawed ; 
outer branch short, 8-jointed ; three following pairs with both branches 3- 
jointed. Fifth pair elongated, 2-jointed. Ovisac single. 
1. Idya furcata, Baird. Pl. VIIL, figs. 1-8. 
(For synonymy of this species, see Brady's Mon. Brit. Cop., vol. ii., p. 172.) 
Body elongated, somewhat pyriform; rostrum short and obtuse. An- 
terior antennæ 8-jointed, first four joints much stouter than last four; their 
comparative length is tabulated by Brady as follows :— 
: 2, 3, 4, 5, 6, 7 8, 
10. 18. 13. 8. i i 2. 8. 
This character is said by Brady, Claus and others to vary considerably, but 
the following taken from my own specimens shows almost the same relative 
lengths except in the fourth joint, viz. -— 
1 3 
, 2 , , 4, 5, 6, 7, 8, 
SRD contenant REA URN d 
14. wW b 4 5. 8. 9. 
