662 StlBANTARCTlC ISLANDS OP NEW ZEALAND. [Crustacea. 



Haplophthalmus australis, sp. no v. 



Body oblong-oval, about half as broad as long, the epimeral plates of the 

 peraeon being large and projecting horizontally, those of the first four segments 

 somewhat widely separated. The head with the front triangularly rounded and 

 tipped with small denticles, two rounded tubercles being situated about the centre 

 of the head and an indistinct longitudinal ridge on each side ; lateral lobes small and 

 subacute. Dorsal surface of the peraeon moderately convex, each segment with the 

 surface somewhat roughened, and bearing a number of rounded tubercles ; these form 

 a fairly well marked median ridge and a less well marked lateral ridge on each side, 

 with indications of another poorly marked ridge one each side external to this. 

 Surface of the pleon (fig. 17^') without tubercles, first three segments short, the first 

 two without epimeral projections, the third with very small narrow epimera, fourth 

 and fifth with epimera large and well developed, terminal segment broad, triangular, 

 posterior border, straight. 



Antennae with the fourth joint of the peduncle as long as the two preceding 

 and rather shorter than the filth ; flagellum almost as long as the fifth, consisting 

 of four or five joints, the last tipped with a pencil of long setae ; the whole antenna 

 covered with fine short setae. Uropoda with the branches equal in length, but the 

 inner slightly more slender than the outer ; both covered with fine setae, and tipped 

 with a pencil of long hairs. 



Length, 6 mm. ; greatest width, 2-5 mm. 



Colour. — Lightish-brown, 



Hob. — Campbell Island, on decaying wood and at roots of plants. 



Type in Canterbury Museum, New Zealand. 



The animal runs with great rapidity, and, although several were seen, I was able 

 to secure only a very few specimens ; further specimens were, however, afterwards 

 obtained by Messrs. Chambers and Des Barres. 



Another species, Haflophthalmus helmsii, Chilton, has been described from Grey- 

 mouth, in New Zealand. It differs from the generic characters given by Sars in 

 having the first three segments of the pleon short and without epimeral expansions. 

 In the present species the first three segments are also short, the first two quite with- 

 out epimeral expansions, but the third has very small narrow expansions ; in this 

 species, too, the eyes consist of three ocelli, instead of only one, as given in Sars's 

 description ; there are also some slight differences in the maxillipedes, which approach 

 still more closely than in other species to those of Trichoniscus. 



It would be easy, and perhaps justifiable, to place the New Zealand species under 

 a new genus, and I had at one time thought of doing this, in the belief that all the 

 southern species would differ from the northern species in the points mentioned. 

 I have, however, an undescribed species from Tasmania which agrees with the 

 northern species of Haplofhthalmus in having only the first two segments without 

 the epimeral expansions, while, as I have pointed out above, H. australis is to some 

 extent intermediate as regards the characters of the pleon, and, as there are only a 

 few species hitherto described in this genus, I prefer to slightly widen the generic 

 characters rather than to create a new genus. 



Sars has pointed out that Haflofhthalmus comes very near to Trichoniscus, and 

 the species now described approaches still nearer, in having the eyes formed of three 

 ocelli and in the character of the terminal portions of the maxillipedes. 



