RAIIDJE. 47 



upper and lower portions confluent. Colour dull reddish olive 

 above, whitish below. A white spot near each side of the posterior 

 end of the head, another above the end of the ventral, and generally 

 a third at the root of the caudal ; ventral with a white edge. 



Hal. Seas of India to the Malay Archipelago, China and 

 Japan. This species attains at least ten inches in length. 



Family IV. 



Disk broad, rhombic ; tubercules or spines usually present. 

 The pectorals extend to the snout. The body passes gradually 

 into the tail, which has a longitudinal fold on either side. No 

 serrated caudal spine. Electric organs absent *. 



In the year 1815 Colonel Montagu drew attention to a sexual 

 character which was observable in some species of these fishes, in 

 which the teeth were blunted in the females and pointed in the 

 males. Another sexual character is that of spines on the body 

 which are temporarily developed during the breeding-season. 



Geographical Distribution. Seas of both hemispheres, but more 

 numerous in the northern ; it possesses but few representatives 

 along the coasts of India, and seems to be absent from the Bed 



1. Genus PLATYRHINA, Miiller & Henle. 



Disk rhombic, with a fold on either side ; tail distinct. Nasal 

 valves distinct. Two dorsal fins on the tail ; caudal well developed ; 

 ventrals separated one from the other. Body covered with rough 

 asperities and spines. 



Geographical Distribution. Seas of India to China and 



50. (1.) Platyrhina schonleinii. 



Platyrhina schonleinii, Mull, fy Henlt >, Plagios. p. 125, t. xlv ; Day, 

 Fish. India, p. 735 (see synon.)- 



Disk subcircular; snout obtuse; tail as long as the disk. Den- 

 tal plate undulating; three elevations in the lower and three 

 corresponding depressions in the upper jaw. Nostrils wide apart. 

 A row of strong spines and also smaller lateral ones along the 

 median line of the back and tail ; some more along the edge of the 

 orbit and on the shoulder. Colour brown, covered with light 

 blotches ; said sometimes to have dark cross bands and large dark 

 spots. 



Hab. Coromandel coast of India. A male example, 27 

 inches in length, was in the Madras Museum. 



* See remarks to genus Narcine, p. 45, ante. 



