82 BRITISH FRESHWATER FISHES 



may be, it is certain that if Char were to die out 

 in the next few thousand years at the same rate as 

 they have done in the last century they would 

 remain only in a very few lakes in the British Isles, 

 and if, for example, these were Girlsta, Killin, 

 Llanberis, and Melvin, all zoologists would agree 

 that our Char were four well-marked species. The 

 extinction of annectant or intermediate types can 

 hardly be said to lead to the formation of species, 

 but it certainly leads to their recognition. 



Some of the characters used in the distinction of 

 the species will appear in the following : — 



Synopsis of the British and Irish Species of 

 Char 

 I. British Species 



A. Body moderately elongate, the greatest 

 depth rarely more than one-fourth or 

 less than one-fifth of the length (to the 

 base of the caudal fin). 



I. Adult males ^ with the snout conical 

 or subconical, more or less acute, 

 and with the lower jaw pointed 

 anteriorly, rarely slightly shorter 

 than the upper and sometimes 

 projecting beyond it. 



a. Interorbital region more or less 

 convex, except in young 

 specimens; teeth moderate. 

 a. Maxillary never ex- 

 tending far beyond 

 the eye. 



^ Young specimens and females usually have the snout 

 blunter and the lower jaw weaker. 



