38 



Memoirs of the Indian Museum. 



[Vol. II, 



of the tail, where they greatly outnumber the rounded tubercles and finally take 

 their place altogether. The whole of the tail is covered with spines of various 

 sizes. 

 Mouth. — Upper jaw more distinctly undulated than the lower. Teeth white, practi- 

 cally lozenge-shaped. 



This specimen was taken near the shore at Malpe, S. Canara, on the Malabar 

 coast. Mr. E. Thurston has kindly given me the following note as to its history : — 

 ' ' I was summoned from the dinner-table to inspect the carcase of an immense skate, 

 whose last act, as she lay dying on the shore, was to continue the species by bringing 

 forth twelve young ones, who were promptly salted.' ' 



Genus Pteroplatea, Müller and Henle. 

 Disk very broad in comparison with its length, lozenge-shaped, fiat. Pectorals 

 imited in front. Tail feeble, normally with a serrated spine, without a rayed 

 caudal fin, a small rayed dorsal fin sometimes present. Teeth with a saddle- 

 shaped base and one or more backwardly-directed, sharp cusps. No processes 

 on the floor of the mouth. Nasal valves coalescent. Skin naked or nearly so. 



, P. zomira ; C, P. tentaculata. 



A. B. 



Fig. 8. — Teeth of Pteroplatea (enlarged) : A, P. micrura; 



Day describes only one Indian species of this genus, but three are common in the 

 Bay of Bengal, namely, P. micrura, P. zonura and P. tentaculata. They may be dis- 

 tinguished as follows : — 

 I. No dorsal fin. 



A. No tentacle on the posterior margin of the spiracle. Dorsal surface 

 uniformly coloured in the adult . . . . P. micrura. 



II. A small dorsal fin on the tail. 



A. No tentacle on the margin of the spiracle. Dorsal surface minutely dotted 



with dark green and boldly spotted with greenish yellow P. zonura. 



B. A small tentacle present behind the spiracle. Dorsal surface spotted and 



blotched with greenish yellow . . . . P. tentaculata. 



