Dr. A. Gunther on a new Species of Black-fish. 47 



previously drawn a pencil sketch of the fish, which he kindly 

 communicated to me as soon as I had informed him that the 

 specimen was different from the other known species. It was 

 evident from this sketch that the head of the specimen had been 

 deformed by stuffing, but that the elongated form of its body is 

 a natural character. The chief difference, however, from Centro- 

 lophus pompilus is in the increased number of the anal rays, 

 which amount to thirty in the present specimen, while they 

 vary between twenty-three and twenty-five in all the specimens 

 of G, pompilus which have hitherto been examined. I have 

 therefore no doubt about its specific distinctness, and propose to 

 call it Centrolophus britannicus, not because I think it is confined 

 to the British seas, but because it has been observed first on the 

 British coast. The characters by which the three species of 

 Centrolophus may be readily distinguished are, shortly, the 

 following : — 



Centrolophus britannicus. The height of the body is one-fifth 

 of the total length ; dorsal fin with 45, anal with 30 rays. 



Centrolophus pompilus. The height of the body is one-fourth 

 of the total length; dorsal fin with 39-41, anal with 23-25 

 rays. 



Centrolophus ovalis. The height of the body is one-third of 

 the total length ; dorsal fin with 40, anal with 24-27 rays. 



A further question arises, whether our new species has not 

 been indicated by one of the earlier writers, or whether it has 

 been confounded under the numerous denominations considered 

 as synonyms of C. pompilus. The circumstance that the four 

 specimens of the Black-fish observed on the British coast, and 

 proved to belong to the genus Centrolophus, have been found on 

 the coast of Cornwall, might lead to the unfounded supposition 

 that the fish is peculiar to this part of England. I think it 

 receives explanation from the fact that the ichthyology of Corn- 

 wall has been worked out more completely than that of any other 

 part of the south coast of Britain, — first by Borlase, from the 

 papers of Mr. Jago of East Looe, and afterwards by so excellent 

 and indefatigable an observer as Mr. Couch. Jago observed 

 two of the four specimens caught together in one net ; and the 

 accurate figure given by Borlase*, and the statements of the 

 relative measurements f, of the distance of the commencement 

 of the dorsal fin from the snout, &c, afford ample proof that 

 those two fishes were not the C. britannicus, but belonged to the 



* Borlase, Nat. Hist, of Cornwall, p. 271, pi. 26. fig. 8. 



t Mr. Couch (Yarr. Brit. Fish. 2nd edit. i. p. 180) appears to have mis- 

 understood Jago's description, in which the fish of thirteen inches is repre- 

 sented as three-fourths of an inch broad. Jago intended to give a state- 

 ment of the horizontal width, and not, as Mr. Couch thinks, of the depth 

 of the body. 



