14 Memoirs of the Indian Museurii. ;Voi,. Ill, 



Genus Tetrodon, Linn. 



Tetrodon inermis, Schlegel. 



A specimen of this species was taken by the " Golden Crown" off the mouth of 

 the Eastern Channel (R. HughH), in November, 1909. The sides of the fresh speci- 

 men are of a bright golden-green colour. 



Tetrodon lunaris, Bloch and Schneid. 



There seems to be every gradation between T. lunaris and T. spadiceus, Richard- 

 son. The only difference is the extent to which the spines on the dorsal surface 

 extend backwards. T. lunaris is one of the commonest species in the Bay and was fre- 

 quently taken on the ''Golden Crown." Yoimg individuals from 2 cm. in length were 

 taken in large numbers on the shore at Puri at the commencement of February, 1909. 

 In fresh specimens the back is dark bluish or greenish grey, sometimes obscure!}' 

 marbled with a paler shade. The sides and belly are white. 



Tetrodon oblongus, Bloch. 



A common species in the Bay of Bengal frequently recorded on the " Golden 

 Crown." 



The length of the largest specimen is 28 cm. 



Tetrodon spinosissimus (Tate Regan). 



(Plate i, fig. 2.) 



Spheroides spinosissimus, Tate Regan, Trans. Linn. Soc. Lond. (2) Zool., vol. xii, 

 partiii, p. 253, pi. 31, fig. 5. 



There are two specimens in the collection of the Indian Museum from the Gulf of 

 Martaban, taken by the "Investigator" from a depth of 100 fathoms. They differ 

 from Tate Regan's figure in having very much shorter spines, and one of them has 

 numerous small black dots on the tail. 



Several specimens from Hongkong agree closely with the original figure. 



The species may be distinguished from ali those described by Day, in the group 

 with two nasal apertures on each side, by the uniform pale brown coloration of its 

 dorsal surface. 



Tetrodon patoca, Ham. Buch. 



Two large specimens were taken by the "Golden Crown," one off the Orissa coast 

 in August, 1908, the other off Gopalpur (Madras Presidency) in September, 1909, the 

 latter measuring 14I inches in length. The species is common in the estuaries of the 

 Ganges. 



There are also several small specimens from Karachi in the collection. In these 

 the pale spots are somewhat obscure. This, however, may be due to the fact that 

 they were originally preserved in formalin. 



