100 THE ZOOLOGIST. 



absences from the nest were due to my presence, which I made 

 as unobtrusive as I was able to. They were sometimes longer 

 when I have every reason to suppose that she was quite uncon- 

 cerned, and vice versa. Also, she showed no apprehension, but 

 sat fast whilst three of us were putting up the tent. Assuming 

 the eggs to have been addled, the conduct of the bird can be 

 explained by supposing that she suspected or was becoming 

 aware of this fact. Birds do become aware of it, and at last 

 leave the eggs, in consequence, nor is there any evidence of the 

 date when these were abandoned, or, indeed, that they were 

 altogether abandoned a month or more afterwards, on my 

 return, though I thought they were. 



(4) The proprietor of the eyrie told Sigurdsson that the eggs 



of these Eagles were often addled (a fact which would be 



discovered by the daring purchaser on blowing them, or even 



before), that one could not say, from year to year, whether 



they would be or not, but that they were seldom good, two 



years running. This is a positive statement, and tallies with 



a similar one made to me, in regard to another pair, by a 



man who had exact knowledge of the facts, viz. that the eggs 



laid for six years in succession were infertile. In this case 



the female was thought to be very old, and from her greater 



hoariness, I may assume that the one in question was aged also. 



If I really caused the eggs to be abandoned, I am extremely 



sorry — I was vexed enough at the time — but I do not think this 



is likely in itself, and, in fact, I have given another explanation 



which must be held to be more than likely, since it is a known 



one. The tent was placed as far off as the conditions permitted 



— I would have preferred its being at twice or even three times 



the distance, but this was impossible without rounding a bend 



of the cliff which put the eyrie out of sight. It was, indeed, a 



bad place for observation. As I have said, the tent was (and 



daily and nightly I wished it wasn't) a " Mommery," of, I 



believe, the smallest size obtainable, made of green Willesden 



canvas, over which was a netting, in the meshes of which moss 



from round about was plentifully stuck. It was close against a 



great rock of cottage-like proportions, and I am tolerably sure 



that the birds did not mind it much in itself — the female most 



certainly did not. In conclusion, I may say that if I had not 



