TORPEDO. 127 



At first the attempt to apportion to those supposed species 

 their true distinctive characters was built upon an attention to 

 the remarkable spots, usually five in number, which are often 

 placed in regular order on the surface of the disk; the absence 

 or orderly arrangement of which was supposed to constitute 

 the definite mark of a species. But it has been found by 

 observation that in fishes in other respects closely resembling 

 each other, these spots, as well as the general colour of the 

 surface, are exceedingly liable to vary; and that in many cases, 

 and especially in those found on our own coasts, they are usually 

 found wanting; and it is further said that they commonly do 

 not occur in young examples. More extended inquiry may 

 shew that when they occur these spots are more frequent in 

 one species than another, or that when present their arrange- 

 ment may be specific; but these particulars, so far as they are 

 now known, are attended with so much uncertainty that, setting 

 all others aside, I shall confine myself to a single one, which, 

 in our present state of knowledge, appears the least liable to 

 uncertainty; and according to which I form the following 

 arrangement or references: — 



Cramp Ray, with a fringed border to the spiracles, the fringes 

 described as from six to ten in number. 



Torpedo narke, Cuviek. 



" vulgaris, Jonston ; Tab. 9, f. 3, 5, 6. 



" " WiLLOUGiiBY; as described. 



Bloch; pi. 122. Donovan; pi. 53. 

 " " Eisso; pi. 3, f. 4 and 5. T. marmorata 



aud T. Galvani. Torpille vulgaire. 

 Fleming ; Br. An., p. 169. 

 " " Jenyns; Manual, p. 509. 



" " Yakrell; Br. Fishes, vol. ii, p. 543. 



Bale Torpille, Lacepede ; who speaks of it as having 



sometimes a fringed border to the 

 spiracle, as if this were liable to 

 uncertainty. 



Cramp Ray with plain spiracles. 



Torpedo Galvanii, Cuviek. Jonston; Tab. 9, f. 4. 



WiLLOUGHBY; T. D. 4. The tail badly 

 represented. 



