1921.] Fauna of the Chilka Lake : Amphipoda. 531 



Paracalliope fluviatilis was described by Thomson as long ago as 1879. Unfortun- 

 ately his figures were so greatly reduced in reproduction that they do not show 

 clearly the structure of the various appendages and no other figures have yet been 

 published. I have, however, the tracings that were made of Mr. Thomson's original 

 figures for the purpose of reproduction and find that the main points in the structure 

 of the gnathopods and of the telson and uropods are quite clearly shown. A descrip- 

 tion was given by Stebbing in 1906 and on the whole agrees well with the speci- 

 mens. In 1899 Stebbing had established the genus Paracalliope for the species. 

 There is one point in his generic diagnosis that requires alteration, for calceoli are 

 certainly present in the males on some of the basal joints of the flagellum in both 

 upper and lower antennae. The species can generally be easily recognised by the 

 greatly elongated fifth peraeopods and by the peculiar inverted position of the 

 second gnathopod ; this appendage seems to have a very loose articulation between 

 the ischium and the carpus, so that the distal portion of the limb often faces in the 

 direction opposite to the normal one (see fig. 3«). Stebbing has pointed out that 

 this recalls the c urious torsion in the first gnathopod of Trischizo stoma nicaeense. 



I give figures of the wholje animal (fig. 3a) and of the antennae (figs. 3Ô, c) and 

 the gnathopods (figs. 3^, e) which will render a detailed description unnecessary. It 

 is difficult to represent the gnathopods accurately, for as Stebbing points out there 

 are two margins to the palm and the outline therefore varies according to the posi- 

 tion in which the gnathopod is mounted. 



Stebbing places the genus under the family Calliopiidae, and this is probably its 

 proper position, though the elongated fifth peraeopods are peculiar and the characters 

 of the family are somewhat indefinite. It was doubtless from the elongated fifth 

 peraeopods that Stebbing suggested that the species Oedicerus novi-zealandiae Dana 

 was probably identical with Paracalliope fluviatilis. I have, however, pointed out 

 elsewhere that Oedicerus novi-zealandiae is a distinct species and is in all probability 

 identical with the species afterwards described by Stebbing as Carolobatea schneiden 

 (1909, p. 620). 



[Not uncommon on a muddy bottom off shore in the main area. N.A.] 



Niphargus chilkensis sp. nov. 



(Text-fig. 4.) 



Localities : — 



Off Samal Island, 3-15 ft., 22-ix-i3. One. 



Off Barkul, 21-VÜ-13. Two. 



One mile S. of Kalidai. Several. 



4 to 9 miles E.^S. of Barkul bungalow. Several. 



3 to 2 miles S.E. by E.|E. of Patsahanipur. Four. 



similar to those from Chilka Lake and New Zealand. These are stated to have been collected in 

 "shallow water," but there is nothing said as to whether the water was fresh, brackish or marine. 

 Along with them was a single specimen which, though small and perhaps immature, appears to be 

 Photis longicauiata (Bate and Westw.). 



