104 



THE SCOTTISH NATURALIST 



Entirely white birds also occur, but these may be cases of 

 albinism. I got one pure white young bird, which had been 

 captured at St Kilda in August 1910, but I was unable to 

 ascertain whether the eyes of this example were those char- 

 acteristic of an albino, or of the normal type. The feet of 

 this specimen were pale pink. 



At St Kilda the birds begin to leave soon after the 

 young are able to fly. They are to be seen in thousands 

 sailing along the faces of the cliffs, and alighting on their 

 ledges, down to the middle of September. After this their 

 numbers fall off, and practically all have moved out to sea by 

 the end of the month. They return, however, after four or five 

 weeks' absence, and are present all the winter. The object in 

 seeking the main is, in my opinion, to go through the 

 process of moulting there. None of the examples secured 

 by me in September show signs of moulting, but a bird 

 obtained in the first week of November exhibits unmistakable 

 traces of having just passed through its change of plumage. 



A LIST OF THE ANTS {HETEROGYNA OR 

 FORMICIDAl) OF THE FORTH AREA. 



By William Evans, F.R.S.E. 



THERE is a growing tendency among those who work at the 

 British Fauna from the distributional standpoint to adopt the 

 Watsonian system of counties and vice- counties so long 

 employed by the botanists. The section of our fauna that 

 has been most thoroughly worked on these lines is the Land 

 and Freshwater Mollusca ; and, as regards Scotland, there 

 are Mr Balfour Brown's recent papers on the Water-beetles, 

 and my list of the Dragon-flies. Now there is promised 

 shortly the distribution of the British Ants on the same 

 lines, by Mr Horace Donisthorpe, and it is in connection 

 with his work that the following records for the counties 

 falling within the Forth drainage area have been put 

 together. They are for the most part based on specimens 

 collected by me ten to fifteen years ago, and form part of the 



