igi6.] 



Fauna of the Chilka Lake : Fish. 



407 



In the collection there is only one skull with the rostrum, collected in December, 

 1 914 at Nalbano Island. This is the only record we possess of a sawfish in the lake. 



The rostrum from the eye to the tip measures 26-5 mm. There are 26 teeth 

 on the right and 23 on the left. The teeth on the left side nearer the head are most 

 irregular. The width of the rostrum in the middle portion is nearty uniform, being 30 

 mm. At the tip it is only 17 mm. and at the base 50 mm. 



This species appears to be only an occasional visitor to the lake. 

 Distribution : — Tropical and temperate seas, the Red Sea, the Indian Ocean and 

 beyond. 



Family TRYGONIDAE. 

 Genus TRYGON, Cuvier. 

 Trygon uarnak (Forskâl). 



Rata uarnak, Forskâl, Descript. Anim., pp. viii, ix. 



Trygon uarnak, Day, Fish. Ind., p. 737 (in part). 



Trygon uarnak, Day, Faun. Brit. Ind., Fish., I, p. 53 (in part). 



Trygon uarnak, Annandale, Mem. Ind. Mus., II, p. 22, pi. i, figs. 1 and 2; pi. ii. figs. 1 and 



ia ; pi. iii, fig. 2C. 

 Trygon uarnak, Günther, Sudsee Fische, III, p. 492. 

 Dasybatus itarnak, Garman, Mem. Mus. Comp. Zool. (Harvard), XXXVI, p. 376. 



There is only one young specimen (female) in the collection ; it was purchased 

 from a fisherman at Satpara. The dorsal surface is covered with round and black 

 spots on a greyish white ground. The measurements of the specimen are given 



below: — 



Breadth across disk . . . . . . . . 290 mm. 



!775- 

 1878. 

 1889. 

 1909. 



1910. 



Tip of snout to root of tail 

 Mouth to vent 

 Length of tail 

 Breadth of the mouth 

 Interorbital space . . 

 Length of snout 



264 



177 



720 



25 



49 



71 



The species is a permanent inhabitant of the lake, in the shallower parts of which 

 it is common. 



Distribution: — Indian Ocean, Red Sea, Gulf of Siam, Bast Indies. 



Trygon pareh, Bleeker. 



1851. Trygon pareh, Bleeker, Verhand. Batav. Genoots., p. 71, t. xxiv. 



i860. Trygon ellioti, Blyth, Journ. Asiat. Soc. Bengal, xxix, p. 41. 



1865. Trygon pareh, Duméril, Hist. Nat. Poiss., I, p. 590. 



1909. Trygon alcockii, Annandale, Mem. Ind. Mus., II, p. 27, text-fig. 3. 



This is a medium-sized Trygon, the disk of which is slightly broader than long, 

 with the pectoral angles rounded. The snout is pointed and forms nearly a right 

 angle at its extremity. The interorbital distance is contained about one and half 

 times in the length of the snout and four and a half times in the length of the disk, 

 which is moderately flat. Of the four specimens collected a young one has a smooth 

 central dorsal tubercle and another behind it, surrounding which there is a group of 



