642 SUBANTAEOTIC ISLANDS OP NEW ZEALAND. [Crustacea. 



row of about six setae and is very slightly produced, forming a narrow pellucid area ; 

 the carpus is triangular, of the usual shape, and is produced posteriorly into a some- 

 what irregular pellucid lobe, on the inner side of which arise three long setae ; there 

 is also a very slight indication of a pellucid lobe on the posterior margin of the merus. 

 Second gnathopod (fig. 10c) of usual shape, the finger very short, the lobe of the 

 propod being produced far beyond its extremity. The third peraeopod is shorter 

 than the fourth, and in each the basos is rather narrow oval. The fifth peraeopod 

 is slightly longer than the fourth, and both are considerably elongated, in large 

 specimens being about three-fourths the length of the body. The uropoda and telson 

 of the usual form. 



Length, 16 mm. 



Hah. — Snares, five female specimens (Gr. R. Marriner). Also found in Stewart 

 Island. 



Type in the Canterbury Museum, New Zealand. 



This species seems very peculiar in possessing a fairly large and well-developed 

 subchelate first gnathopod in the female very different from the usual form of 

 this appendage, and more nearly resembling what is generally found in the second 

 gnathopod of the male. I have only about five or six specimens, but from these it 

 appears that this form of gnathopod is only well developed when the female is mature, 

 as the smaller specimens have the propod of the first gnathopod much more slender 

 and more of the usual type, and in the smallest specimens the propod is of ap- 

 proximately the same width throughout, not being dilated at all, and the palm is 

 transverse or only very slightly oblique. 



I have long had from the north of Auckland a single imperfect female specimen of 

 a Parorchestia which resembles the species now described in having the propod of the 

 first gnathopod dilated and distinctly subchelate ; it differs, however, in having the 

 propod suboblong, with a transverse palm. I had hitherto looked upon it as an 

 abnormal specimen of P. sylvicola, but the existence of a somewhat similar form 

 on the Snares shows that it may perhaps belong to a distinct species. 



Since the above description was drawn up Mr. G. M. Thomson has handed over 

 to me all the notes and drawings of Amphipoda that he has accumulated during many 

 years past, and among them I find drawings made years ago of the gnathopoda 

 of an undetermined species of land-hopper from Port Pegasus, Stewart Island, which 

 correspond closely with a somewhat immature female of Parorchestia improvisa, and 

 evidently belong to that species, so that this species occurs on the mainland of 

 New Zealand as well as at the Snares. 



Parorchestia tenuis (Dana). 



Orchestia tenuis, Dana, P. Amer. Ac, ii, p. 202, 1852, and U.S. Expl. Exped., 

 xiii, ii, p. 872, pi. lix, fig. 1, 1853 and 1855. Parorchestia tenuis, 

 Stebbing, " Das Tierreich Amphipoda," p. 557, 1906 ; Chilton, Trans. 

 N.Z. Inst., xli, p. 58, 1909. 



I have a few small specimens, obtained on the sea-shore of Perseverance Har- 

 bour, Campbell Island, at the mouth of a small fresh-water stream, that I think 

 belong to this species, as defined by Stebbing ; they are the same as specimens from 

 brackish and fresh-water streams in various parts of New Zealand. Although this 

 species agrees with Stebbing' s description of the genus Parorchestia in having a small 



