Revision of the Irish Char. 227 



In 1802 and 1863 Dr. Giinther described the char of 

 Lough Melvin and Lough Eask as Salmo grayi and S. colli 

 respectively. Since that time no serious study of the Irish 

 char has been attempted, but most writers have agreed in 

 regarding all the char of the British Isles as forms of the 

 northern migratory S. alpinus, L. If this be so, I have no 

 hesitation in saying that all char (S. fontinalis possibly ex- 

 cepted) must be included in S. alpinus, and I think it "is 

 simpler to keep to the binomial nomenclature and to call the 

 Lough Melvin char Salvelinus grayi m preference to Salvelinus 

 alpinus grayi or Salvelinus alpinus, var. grayi. In either 

 case, whether we recognize only one species of char, Salve- 

 linus alpinus, or numerous species, S. grayi, S. colii, &c, 

 the species is by no means equivalent to species such as 

 Esox lucius or Leuciscus rutilus, which have probably persisted 

 unchanged during the whole of the time that the evolution of 

 the Salvelini has been taking place. 



The present revision is based on the specimens in the 

 British Museum and also on the collection of the Dublin 

 Museum, kindly sent to me on loan. 



Synopsis of the Species. 



I. Snout conical, pointed; jaws equal anteriorly or the lower slightly 



projecting'; lower jaw pointed ; 13 or 14 gill-rakers on the lower 

 part of the anterior branchial arch ; interorbital region more or le^s 

 convex. 

 Teeth moderate; snout 1^ as long as eye (in a specimen 

 of 280 mm.), less than interorbital width, which is 

 3 in the length of head; 186 scales in a longitudinal 



series * 1. schaiffi. 



Teeth strong; snout \\ as long as eye (in a specimen 

 of 205 mm.), slightly more than interorbital width, 

 which is 3^ in the length of head ; 165 scales in a 

 longitudinal series 2. trevelyani. 



II. Snout subcorneal, decurved ; jaws equal anteriorly, the lower more 



or less pointed. 



A. 12 to 16 gill-rakers on the lower part of the anterior branchial 

 arch ; interorbital region more or less convex, its width 3 (adult) 

 to 3^ (young) in the length of head. 

 Depth of body 4 to 5 in the length ; least depth of 

 caudal peduncle about f the length of head ; pec- 

 toral fin extending \ to f of the distance from its 

 base to the origin of pelvics ; 138 to 168 scales in a 

 longitudinal series 3. colii. 



* The number of scales in a longitudinal series is counted above the 

 lateral line and does not include the scales covering the base of the caudal 

 tin. The scales descend to the lateral line in regular oblique series and 

 are easily counted. 



16* 



