666 SUBANTAECTIC ISLANDS OF NEW ZEALAND. [Crustacea. 



rather more than half as long as the outer, which is more tha-n twice as long as the 

 peduncle, both ending in a few fine setae. 



Colour. — Pale-yellowish, with the dorsal surface more or less darkly pigmented. 



Length, 10 mm. ; greatest breadth (of female), 5 mm. 



Hah. — Campbell Island, abundant on the shore of Perseverance Harbour about 

 high- water mark ; Ewing Island (Dr. L. Cockayne). 



Type in Canterbury Museum, New Zealand. 



This species differs from S. waitatensis, which is found on the coasts of the South 

 Island of New Zealand, in being much larger and broader (in the female) and in 

 having the surface of the body less tuberculated ; there are also slight differences 

 in the antennae and some of the mouth parts, 



The mouth parts are, on the whole, similar to those of S. waitatensis, but in the 

 first maxilla (fig. 186) the outer portion approaches somewhat more nearly to the 

 normal type — viz., it bears at the end a number of stout slightly curved setae, suc- 

 ceeded by more slender setae on the inner side ; the outermost one, however, is 

 thickly fringed on its outer margin with long fine setae curving slightly inwards, 

 giving the same general appearance as in S. waitatensis, in which, however, the stout 

 setae appear to be absent and the joint ends in a rounded lobe fringed with the long 

 setae. The maxilliped has the palp with the various joints of which it is composed 

 rather better indicated than in S. waitatensis. The other mouth parts call for no 

 special attention. 



The male differs from the female in having the body much narrower, but there 

 seem to be no secondary sexual characters in the legs or other appendages. The 

 first pleopod of the male (fig. ISd) is specially modified, the exopod is small and of 

 the usual shape, but the endopod is developed into a strongly chitinized organ which 

 appears to be unjointed and to be fused with the basal portion of the pleopod ; it 

 is more than twice as long as the exopod, and curves outwards towards the end, 

 which narrows somewhat abruptly to the acute termination ; the single male organ 

 appears more or less fused with the first pleopod, and is seen in the median line as 

 a small narrow appendage less than half as long as the endopod. In the second 

 pleopod (fig. 18e) the endopod is two-jointed, the first joint short, broader than 

 long ; the second joint reaching as far as the end of the exopod, narrowly triangular 

 in shape, and ending acutely ; the exopod is articulated to the protopod towards 

 its outer border, and forms a flat opercular lamella, with the inner margin strongly 

 curved, the outer margin concave towards the end (which is fringed on both sides 

 with fine setae) and convex near the base. In the third pleopod (fig. 18/) the 

 endopod is branchial in. structure, nearly rectangular, with the angles rounded, and 

 is not quite half as long as the opercular exopod, which has the same general shape 

 as in the second pleopod, but is broader towards the distal end. The fourth and 

 fifth pleopods are similar to the third. 



Genus Deto, Guerin, 1834. 

 Distribution. — Widely distributed in subantarctic regions. 



Deto aucklandiae (G. M. Thomson). 



Actaecia aucklandiae, G. M. Thomson, Trans. N.Z. Inst., xi, p. 249, 1879. 

 Scyphax (?) aucklandiae, Chilton, Trans. Linn. Soc, viii, p. 126, pi. xv, 



