46 



CLASSIFICATION OF FISHES. 



up/ but in so mutilated a condition that to this day 

 they are most imperfectly known. We aUude to the 

 Gymnetrus Hawkensii, figured by Bloch^ and to slight 

 notices of one^ if not of two other and diflPerent species 

 upon record. Those which are more strongly constructed, 

 form the aberrant groups ; and of these, among the 

 rarest of our fishes, are the Cepola and the Ophidium ; 

 although both genera are common in the Mediterranean. 

 (48.) The annexed outline of the Xiphicfhis Russellii 

 Sw., or the blade-fish of India, wiUgive the reader a better 



idea of the general character of these extraordinary fishes 

 than the most laboured anatomical description. Notwith- 

 standing the excessive length of the body, which reaches 

 to 2 feet 8 in., it is so thin that itmay well be compared to a 

 straight sword-blade, highly pohshed or burnished with 

 silver. The form of the body, or at least its length, varies 

 in the different genera ; but in all that have yet been dis- 

 covered, excepting one, the dorsal fin extends the whole 

 length of the back : this fin is often very broad, or 

 more properly high, and its rays are so slender and 

 fragile as almost to break on the slightest handling. 

 The head is always excessively obtuse, the profile being 

 obliquely vertical, so that it would seem a^ if the snout 

 had been cut off : the belly is so long, that the vent is 

 close to the extremity of the body, and this accounts 



