Parkek. — On a Torpedo recently caught near Dunedin. 283 



Similarly in T.faircJiildi, the first dorsal is said by Hutton to be " over 

 the ventrals, with the posterior edges of both in a hue," and to be " about 

 one and a half times the size of the second." 



Unfortunately it is not stated by either Gimther or Hutton whether by 

 " size" is meant area, or greatest length, or vertical height, or length of 

 base ; nor whether, in giving the position of the first dorsal with regard to 

 the ventrals, its base or line of attachment should, as one would naturally 

 think, be made the standard. A reference to fig. 3 (pi. xxii.) will show the 

 necessity of a strict definition of terms, in a case where such apparently 

 insignificant differences are considered as of specific importance. The 

 figure shows the two dorsals of T. fusca of the natural size, and it will be 

 seen that while the line of attachment (a b), and the vertical height (c d), of 

 the first dorsal are almost exactly twice the corresponding dimensions (a' b', 

 c' d') of the second, yet the greatest length {a c) of the first is considerably 

 less than twice that of the second (a' c'), the proportions of the two being, 

 in fact, as 13 to 8. The figure also shows that the actual posterior boun- 

 dary of the first dorsal (c) projects considerably beyond the posterior end of 

 the base (b), and that it is therefore important to state which of the dis- 

 tances a b and a d is to be taken in considering the position of the fin with 

 regard to the ventrals. 



It is rather strange that the peculiarity of the caudal fin of Torpedo is 

 not mentioned in the " Catalogue of Fishes " : it is certainly worthy of 

 notice that, although belonging to an order in which heterocercality is the 

 general rule, Torpedo has a tail-fin which is diphycercal, at the same time 

 simulating in a remarkable way the homocercal tail of a Teleost. 



The characters of the specimen described are as follows : — 

 Torpedo fusca, ? n. sp. 

 PI. xxii., fig. 1. 



Spiracles not fringed, then distance from the eyes little more than then- 

 own diameter. The greatest length of the first dorsal fin (fig. 3) is to that of the 

 second as 13 is to 8 : the base and the vertical height of the first dorsal are 

 almost exactly twice those of the second. The posterior end of the base of 

 the pelvic fin is nearly opposite the middle of that of the first dorsal. No 

 distinct longitudinal pit at the angle of the mouth, but several irregular 

 folds (fig. 2). The length of the band of mandibular teeth has the same 

 proportion to the gape as in T. narce. Dark brown above, mottled with 

 irregular lighter patches : greyish-brown beneath. 



Total length 26-0 inch. 



Length of disc 

 Breadth of disc 

 Length of electric organ 

 Average breadth of organ 



16-5 



14-0 



7-5 



2-5 



