Studies on the New Zealand Amphipodan Fauna No. 2. The Family Talitridae: The Fresh-Water Genus Chiltonia Stebbing * This study is part of an investigation carried out at Victoria University College, Wellington, with the aid of a New Zealand University Research Fund Fellowship. By D. E. Hurley, Portobello Marine Biological Station, Port Chalmers. [Read by title before Otago Branch on April 14, 1953; received by Editor, April 29, 1953.] Summary Keys are given to the genera of Talitridae and the New Zealand species of Chiltonia. Chiltonia mihiwaka (Chilton) is re-described and figured Two new species, Chiltonia rivertonensis from Riverton, New Zealand, and Chiltonia enderbyensis from Enderby Island, Auckland Islands Group, are described. The New Zealand species of this fresh-water genus have the male first pleopod peculiarly and differently modified for each species. Introduction and Acknowledgments The Family Talitridae, which is represented in New Zealand by over 30 species, more than any other family, is not a group showing great distinction in general facies. In fact, the species are monotonously similar. Yet species of the family have successfully invaded both fresh-water and terrestrial habitats As well, there are in New Zealand a number of supralittoral (as defined by T. A. and A. Stephenson, 1949) and inter-tidal species. The genera fall into three or possibly four complexes which can be associated with these differing environments—the inter-tidal species, the supralittoral-terrestrial and the fresh-water species. Within these complexes, the genera tend to intergrade morphologically, making for systematic difficulties at the generic level. However, the sole New Zealand fresh-water genus, Chiltonia, stands apart from the others, compact and clearly distinguishable. The Talitridae belong to the Sub-order Gammaridea; three sub-orders of amphipods being represented in New Zealand. The Gammaridea are easily distinguished from the Cyamidea, comprised of the greatly modified Caprellidae and Cyamidae (or whale-lice). The third sub-order, the Hyperiidea, embraces the large-eyed pelagic amphipods in which the maxilliped palp is lacking. Most representative of the family are the common sand-hoppers. Guides to family identification are the “typical” amphipod appearance, but lack of any accessory flagella to the antennae, and the usually uniramous condition of the third uropod. Keys to the sub-orders and families of South African amphipods are given by Barnard (1940). They do not include the Family Prophliantidae (Nicholls, 1939), but are otherwise applicable to the New Zealand fauna. I am indebted to the Canterbury University College Council and Professor E. Percival for making available to me the late Professor Chilton's specimens and literature; and especially to Professor L. R. Richardson, under whose supervision