Chilton. — On Nciv Zealand Idoteida3. I'M 



longer than the peduncle, with 12 to 28 joints. Epimera 

 ratiaer narrow, in the second and third thoracic segments 

 scarcely occupying more than lialf the length of the lateral 

 margins, in the fourth to seventh segments occupying their 

 whole length ; only the last two epimera on each side have 

 their postero-lateral angles acute. The legs are robust ; the 

 fourth to seventh pairs of legs have their posterior and outer 

 angles of the meros and ischium produced, and in adult 

 examples spiniform. The posterior plates of the opercular 

 valves are quadrate and nearly square. The length of the 

 largest example in the Museum collection exceeds 2tfin. 

 (o8mm.), but average-sized examples measure about If in. 

 (45mm.)."— [MiEES.] 



All the specimens that I have collected have been green in 

 colour, and were found on green seaweed. 



In this species the female, when bearing eggs in the brood- 

 pouch, has the thorax from the first to the fourth segments 

 more or less expanded, as in Idotca pcronil. 



This is the coimnonest species of Idotca in New Zealand, 

 and is widely distributed in the southern seas, being found in 

 the Indian Ocean, in Australia, on the east and west coasts 

 of South America, Falkland Islands, Cape of Good Hope, itc. 



As stated by ]\Iiers, there is " considerable variation in the 

 length of the flagella of the antennae, the robustness of the 

 legs, and the depth of the posterior notch of the terminal seg- 

 ment and the acuteuess of its postero-lateral angles." From 

 the account of Idotea excavata, Haswell, given below, it will 

 be seen that, if this species is identical with I. uiigtilata, there 

 is also some variation in the amount of coalescence of the 

 posttibdominal segments, as there is also in Idotea peronii and 

 /. elongata. Miers has already suggested tlmt Idotea excavata, 

 Haswell, is probably identical with I. iingulata/'- and, accept- 

 ing this suggestion, Haswell has struck out I. excavata from 

 the list of Australian Idoteidce, though he omitted to put 

 I. ungulata in its place.!' Through the kindness of the 

 Trustees of the Australian Museum, I have been able to obtain 

 specimens of I. excavata from Portland, Victoria, and to com- 

 pare them with New Zealand specimens. Both specimens are 

 small, the largest being 20mm. in length. The abdomen 

 consists of a single segment only, scarcely a trace even of a 

 suture being discernible. They thus differ in a marked degree 

 from New Zealand specimens ; but, in view of the variation 

 in this respect that I show" exists in /. elongata and J. peronii, 

 I am not disposed to place very much importance on this 



* " Zoology of tlie ' Alert,' " p. 311, footnote. 



t " Revision of tlie Australian Isopoda," " Proc. Linn. Soc. N.S.W.," 

 vol. ix., part 4. 



