244 THE GANNET 



and taking into account those old birds which select 

 inaccessible positions," he concludes that 10,000 adult birds 

 would be tolerably near the truth.* 



In 1901 Mr. William Evans concluded after taking 

 observations from different points that Professor Fleming's 

 10,000 was not too high, but in 1904, having done several 

 photographs of the cliffs from the sea, he altered his opinion 

 and rated the strength of the Bass at from 7000 to 8000 

 adult Gannets.f 



Mr. Evans has devoted both time and thought to the 

 matter, and has visited the Bass on several occasions for 

 the express purpose of attempting a census of the Gannets 

 by means of photographs, and his judgment is no doubt a 

 considered one. One of the photographs taken by Mr. 

 Evans having been submitted for examination, I had it 

 minutely scrutinised (after dividing it into four sections), 

 through a large magnifying glass, with the result that it 

 was thought by the scrutineer to exhibit about 960 

 Gannets. Mr. Evans, on the other hand, thought it con- 

 tained as many as 1500. But it is exceedingly difficult 

 to say whether many of the white specks on it are merely 

 whitewashed rocks, on which the birds have been sitting, 

 or the birds themselves. This photograph is considered 



* t.c, p. 395, 



t See " Proc. R.P.S. Edinburgh," 1906-7, p. 63, note. 



