78 BRITISH FRESHWATER FISHES 



Locality Number of VertebrtC 



Loch Baden, Sutherlandshire . .61 



Loyal, „ . . 59, 60, 61, 61, 61, 61 



Scourie „ . . 64, 64 



Stack „ . . 64 



under Ben Hope, Sutherlandshire . 63, 64, 64 



Hellyal, Orkneys . . -59 



Girlsta, Shetlands . . .62 

 Fada, North Uist ... 62 



Lough Luggala, Wicklow . . . 62, 62, 63 



„ Mask, Galway . . .62 



„ Eske, Donegal . . . 62, 63 



,, Melvin, Fermanagh . . 58, 59, 59, 60, 60 



These numbers are interesting in that they show a 

 differentiation of the Sutherlandshire Char into two 

 groups, those with fifty-nine to sixty-one vertebrae 

 in the lochs of the southern and eastern parts of 

 the county and those with sixty-three or sixty-four 

 vertebrae inhabiting the lochs of the north-west ; 

 whilst in Ireland the Char of Lough Melvin seems 

 to be well separated from the rest by the fewer 

 vertebrae (fifty-eight to sixty instead of sixty-two 

 or sixty-three). 



The number of scales in a longitudinal series, i.e. 

 the number of oblique rows of scales running down- 

 wards and backwards to the lateral line, is subject 

 to very considerable variation when a number of 

 specimens from the same locality are compared ; 

 thus in thirty-eight Char from Loch Loyal I count 

 from 126 to 178 scales in a longitudinal series, 

 and these I cannot regard as specifically distinct 

 from the Char of the Lake District, in which I 

 count 160 to 200 scales. However, the number 

 of scales is always important, and in some of our 

 Char is a very valuable specific character. The 



