Chilton. — A New Species of Orchestia. 359 



in whicli the male tends to differ from the female in the dilatation of 

 the meral and carpal joints of the fifth peraeopod, but in it, as to a less 

 extent in 0. chiliensis also, the same tendency is seen in the fourth peraeo- 

 pod as well. 0. miranda differs from 0. chiliensis in the much greater 

 expansion of the joints of the last two peraeopoda, and also in the second 

 gnathopod, which has the palm less oblique and without the large obtuse 

 tooth near the finger-hinge characteristic of 0. chiliensis. It must be 

 remembered, however, that all the examples of 0. miranda at present known 

 come from a single restricted locality ; if it is found to be more wide- 

 spread an examination of specimens from other localities will probably 

 show that the distinctions drawn above between it and 0. chiliensis will 

 not invariably hold. 



Art. XXXIV. — Some Australian and New Zealand Gammaridae. 



By Charles Chilton, M.A., D.Sc, LL.D., M.B., CM., F.L.S., C.M.Z.S., 



Professor of Biology, Canterbury College, New Zealand. 



[Read before the Philosophical Institute of Canterbury, 3rd November, 1915.] 



The following paper deals with a few species of Gammaridae found in 

 Australian and New Zealand seas. Nearly all of them are widely dis- 

 tributed, and show considerable local variation. Hence the delimitation 

 of the species and of their varieties is difficult, and will call for much more 

 investigation than can be devoted to the subject at the present time. 



Three of the species are now recorded from New Zealand f< r the first 

 time. 



Melita festiva (Chilton). Figs. 1 and 2. 



Moeraf estiva Chilton, 1884, p. 1037, pi. 46, fig. 2 ; Stebbing, 1910a, 

 p. 642. Moera rubromaculata Haswell (part), 1885, p. 105. Cera- 

 docus rubromaculatus Delia Valle (part), 1893, p. 720 ; Stebbing 

 (part), 1906, pp. 430 and 732. 



Specific Diagnosis. 



Male. — Peraeon smooth. Pleon with fourth segment produced dorsally 

 into a single tooth, fi^fth segment into 2 small teeth with 1 or 2 cetae. Third 

 pleon segment with postero-lateral angle produced, acute, lower margin 

 bearing 2 setae anteriorly and being indistinctly serrate posteriorly. 



First gnathopod small, merus bearing posteriorly short furry setae 

 as well as some long hairs ; carpus slightly longer than propod, bearing a 

 distinct row of long setae and some furry setae near antero-distal angle 

 and many long setae arranged in short transverse rows on the posterior 

 margin and on the inner surface ; propod somewhat narrowed at the 

 base ; palm short, nearly transverse, hardly defined, tufts of long setae on 

 posterior margin and along the palm, smaller tufts on the anterior margin 

 and at base of finger ; finger curved, acute, fitting closely on to palm 



