iç)i6.] 



Fauna of the Chilka Lake : Fish. 



447 



and Ophichthus microcephalics (Day) so far as the length of the head is concerned. 

 The length of the head in the new species is five and a half times in the length from 

 the end of the snout to the vent, whereas in that of 0. boro it is three and a half 

 to four times and in 0. microcephalus it is seven and one- third to eight. With respect 

 to the length of the tail the new species approaches 0. microcephalus rather than 

 0. boro. 



The new species differs considerably from recently described species of Ophich- 

 thus, viz. 0. miyamotonis, Tanaka, 1 0. asakusae, Jordan and Snyder * ; 0. tsuchidae, 

 Jordan and Snyder 3 ; all from Japanese waters. All of these have much longer 

 heads. The new species in this respect somewhat resembles 0. (B ascanichthys) hemi- 

 zona, Ogilby + of the Australian seas (Port Jackson), but differs from it in all other 

 proportions and in colouration. It also greatly differs from 0. frontalis (Garman) 6 

 and 0. biserialis (Garman). 6 



In the shortness of its head the new species resembles Ophicthus rhytidoderma 

 (Bleeker) , which is the same as the Pisoodonophis rutidermatoides referred to by Kaup , 

 but differs from it totally in the character of its teeth and in other particulars. 



There are two specimens in the collection, measuring twenty-seven and a half 



inches (type) and thirty-two and a half inches (co-type) in total length. Both are 



from Rambha Bay. Some of the important measurements of the two specimens are 



given below : — 



Rambha Bay. Rambha Bay. 



22-VÜ-14. ii-iv-14. 



42 mm. . . . . 66 mm. 



Snout to vent 



. lu gm-upcmiag,) 



237 



Tau .. 



. . 



• • 455 



Diameter of eye . . 



. . 



3 



Length of snout . . 



. . 



6 



Interorbital distance 



. . 



6 



Gill-opening to origin 



of dorsal fin 



13 



Free portion of tail 



. . 



6 





■ • 345 „ 





■ 550 „ 





5 » 





10 „ 





10 ' „ 





24 „ 





8 „ 



The type-specimen, which was collected on 22nd July, 1914, measures 692 mm. 

 in total length and is entered under No. F 1111 in the register of the Indian Museum. 

 The co-type, which was collected on nth April, 1914, is 895 mm. in total length. 

 The fish is a permanent inhabitant of the main area of the lake, being obtainable 

 during the period when its water is almost fresh as well as in the period of its 

 maximum salinity. It does not however breed in the lake. In fact none of the eels 

 do so, for no Iyeptocephalus larvae have been collected during the survey though they 

 are plentiful on the Puri coast. 



1 Tanaka, Fishes of Japan, XI, p. 195 . 



* Proc. U. S. Nat. Mus., XXIII, p. 872, fig. 18. 

 3 Ibid., XXIII, p. 873, fig. 19. 



* Proc. Linn. Soc. New South Wales, XXII, p. 248 (1897). 



5 Mem. Mus. Comp. Zool. Harvard, XXIV, p. 309. 



6 Ibid., XXIV, p. 311. 



