136 



CLASSIFICATION OF FISHES. 



mouth and the branchial apertures being placed com- 

 pletely beneath, — the former under the eyes, the latter 

 under the pectoral fin, — so that neither of them can be 

 seen when the fish is laid upon its belly. These fish, 

 of which there are several species, grow to a large size, 

 and appear to be pelagic, or rovers of the ocean. Some 

 inhabit all latitudes, from the coldest to the hottest ; but 

 no doubt each species has its peculiar geographic range, 

 although none have yet been found on our own coasts. 

 The common species is said to attack whales much in 

 the same manner as the sword-fish ; although it is ob- 

 vious that the snout, being calculated to cut laterally, 

 and not to thrust, must be used as an offensive weapon, 

 in a very different manner : for this reason, we do not 

 believe the assertion that some writers have made, that 

 the snout of the saw-fish has been found driven into 

 the sides of ships like those of the sword-fish ; because 

 any one who looks to this snout, and observes that the 

 end of it is quite blunt, must see such a thing to be 

 altogether impossible. The species often grow to be- 

 tween 18 and 20 feet long, and are chiefly distinguished 

 by the number and form of the tooth-like processes on 

 each side. Klein first made known the singular fact, 

 that in the fcetal or young saw-fish the snout is folded 

 back over the head, and the rudiments of the spines are 

 indicated by tubercles. 



(119-) The third of the aberrant forms in the great 

 family of sharks, is either represented by Squatina, or 

 by Crossorhinus ; both of which differ from all the 

 more typical sharks, in having the mouth at the extre- 

 mity of the muzzle, and not beneath it. That these 

 two forms, as well as Cestracion, are perfectly analogous, 

 there can be no question ; the only difficulty is that of 

 determining their natural situation or affinity. We 

 confess our strong doubts on the propriety of placing 

 Squatina among the sharks, rather than with the rays, 

 to which it has certainly, of the two, the greatest 

 resemblance both in external form and internal structure. 

 Without, however, entering further into this question 



