658 SUBANTAECTIC ISLANDS OF NEW ZEALAND. [Crustacea. 



This species appeared to me to be very closely allied to or identical with Dyna- 

 mene eatoni, Miers, described from Kerguelen Island, and afterwards recorded by 

 DoUfus from South America (" Mission du Cap Horn," Crustacea, p, F 66). 



Dr. Caiman has, however, kindly compared specimens sent to him with co-types 

 of D. eatoni, and finds that, although very closely allied, D. huttoni is distinct in 

 several respects : thus, D. eatoni is much less convex, and has the front margin of 

 the head produced into a marked ridge hardly visible in D. huttoni ; the first segment 

 of the peraeon is much broader as compared with the head ; the third segment of the 

 peduncle of the antennule is longer and more slender, and on the terminal portion of 

 the pleon the sinuous transverse groove found in D. huttoni in addition to the seg- 

 mental grooves which run in from the sides is absent. 



Suborder VALVIFERA. 

 Fam. Idoteidae. 

 Genus Idotea, Fabr., 1798. 

 Distribution. — In all seas. 



Idotea elongata, Miers. 



Idotea elongata, Miers, Ann. & Mag. Nat. Hist., ser. 4, xvii, p. 225, 1876 ; 

 Chilton, Trans. N.Z. Inst., xxii, p. 198, 1890. 



Two specimens, one male and one female, from Musgrave Harbour, Auckland 

 Islands (E. E. Waite). 



The female has the brood-pouch full of eggs, and the anterior segments of the 

 trunk expanded, but not to so great a degree as it is sometimes met with. In the 

 mature female with eggs in the brood-pouch the peraeon is " much dilated in the 

 middle, the second, third, and fourth segments being progressively broader and 

 bluntly angled at the sides, fifth suddenly narrowing to less than half the width of 

 the fourth." The lateral suture on the pleon is often very indistinct, so that the 

 pleon is almost or quite uniarticulate. 



The type specimens of this species are in the British Museum, and came from 

 the Auckland Islands. It is common on the New Zealand coasts, and is always found 

 on brown seaweeds, to which in colour and markings it presents a close resemblance. 



Miers has also recorded it from the Falkland Islands. 



Idotea lacustris, G. M. Thomson. 



Idotea lacustris, Thomson, Trans. N.Z. Inst., xi, p. 250, 1879 ; Miers, Journ. 

 Linn. Soc, xvi, p. 39, pi. i, figs. 11, 12, 1881 ; Chilton, Trans. N.Z. 

 Inst., xxii, p. 194, 1890, and xxiv, p. 263, 1892 ; N.Z. Journ. Sci., 

 U.S., i, p. 131, 1891. 



A few specimens were gathered at Campbell Island : some, collected by Pro- 

 fessor H. B. Kirk, were taken in the lake or lagoon at the south end of the island, 

 into which salt water may be driven at exceptionally high tides ; others were 

 gathered in fresh-water streams by Mr. R. M. Laing at a height of about 600 ft. 

 above sea-level. I have also specimens collected by Professor Benham from a fresh- 

 water creek on Mount Honey in February, 1907. 



