94 PERCY SLADEN TRUST EXPEDITION 



It is possible that the New Zealand species Anthura affinis, Chilton, 1882, may be 

 properly referable to this genus, in which case Miss Richardson's species would require to 

 be renamed, but Dr Chilton's species makes a still nearer approach perhaps to Cyathura 

 carinata (Kroyer). 



7. Apanthura xenocheir, n. sp. (Plate 7 B.) 



The lateral corners of the head are well rounded ; its rostral point is acute. The 

 segments of the peraeon are not very elongate, the third, fourth, and fifth longer than the 

 others. The first six segments of the pleon are short, with their lines of separation not 

 by any means conspicuous, partly owing to the pattern of irregular dark brown spots, 

 with which the whole of the back is diversified ; the corners of the fifth segment exhibit 

 each an outstanding tuft of five plumose setae. Eyes round, dark, close to rounded 

 corners of the head. 



First antennae short, first joint the largest, thud a little longer but narrower than 

 the second, flagellum shorter than the third joint of peduncle, three-jointed, the last two 

 joints minute. Second antennas a little longer than the first, second joint of peduncle the 

 largest, the small flagellum setulose, perhaps three-jointed. 



The mandibles ending bluntly in two transparent teeth or lobes, the palp with a 

 stout middle-joint, the third joint much smaller, fringed with five spines. First maxilla 

 with serrature of three denticles at the apex. Other mouth-parts not well made out, 

 but maxillipeds seemingly in agreement with those of A. sanclalensis. 



The first gnathopods are the distinctive feature of this species. The second joint is 

 as usual distally widened, the third nearly as long as the second, the fourth in coalescence 

 with the fifth forming a small cup-like wrist, the sixth joint or hand massive, the hind 

 margin produced into a strong tooth fringed on its inner side with four spinules, a 

 little cavity being left between it and the circular lobe which covers the base of the 

 finger. Into this cavity the strongly curved but very small finger closes down. In 

 Chilton's Anthura affinis the hand has a small apical tooth, but the finger closes over the 

 tooth to meet a setiferous process of the fifth joint produced along the inner margin of the 

 sixth joint. This is also the case in Cyathura carinata (Kroyer). 



The second gnathopods and the five pairs of perseopods are all almost exactly alike, 

 the second gnathopods and first perasopods confronting the others and having a little 

 advantage in robustness, but this is chiefly over the fifth peraeopods. In the second 

 gnathopods the fourth joint with its outer apex actually reaches the sixth joint, in the 

 following limbs there is a small but successively increasing interval. In all these limbs, 

 however, the small fifth joint has the quality of under-riding the sixth joint at its base. 

 The four pairs of marsupial membranes enclosed in this specimen thirty-three large eggs. 



The first pleopods have a large distally widened outer branch, rather longer than the 

 narrow inner branch which has plumose setae on its rounded apex ; the plumose setae of 

 the outer branch begin at its greatest breadth on the outer margin and are carried a very 

 short distance up the inner. 



The uropods have serrate margins, carrying plumose setae, to the large upper branch 

 which is partially unfolded on the outer side, and a little exceeds the peduncular part 



