^"''S^?'^] ^^i^^^ Pood of European Birds. \\ 



from dung, or consisted of scattered kernels picked up in stubble- 

 fields, he still considers that it must all be counted against the 

 birds, as it shows their taste for grain. This is not fair. Grain so 

 obtained has no value to the farmer and should not be reckoned as 

 a loss. As a matter of fact, Mr. Gilmour's own tables show that 

 the Rooks do not " attack and prey freely upon the farmer's grain 

 whenever and wherever favourable opportunity is presented." 

 Many stomachs taken in harvest time show no grain, and a large 

 proportion of them contained some insects. It cannot be claimed 

 that any of them lacked opportunity to eat grain, for all were 

 collected practically from the same locality. 



In comparing the results obtained by these investigators some 

 important differences are noted, and it is seen that the two have 

 drawn almost diametrically opposite conclusions The Rooks 

 examined by Dr. Hollrung contained 17 mice, an article of food 

 which Mr. Gilmour does not seem to have found in his. The 

 insects, unlike those eaten by the Scottish Rooks, were mostly 

 noxious species whose destruction was a decided benefit to the 

 farmer. While grain was eaten to some extent by Dr. Hollrung's 

 Rooks, it does not appear to constitute an important article of 

 their diet economically considered. 



Mr. Gilmour assumes that the Rooks taken in Fifeshire fairly 

 represent those of the whole of the Lowlands of Scotland in their 

 food habits, an assumption that may possibly be true, but Dr. 

 Hollrung's investigation shows that no such supposition will hold 

 for extensive areas of country. Stomach examination as well as 

 field observation shows more and more that the kind of food taken 

 by birds is determined by availability as well as taste ; conse- 

 quently the food of any particular species will vary to a certain 

 extent in different localities. 



The Common Crow {Corvus americatiiis^ represents in this 

 country, as nearly as may be, the economic position occupied by 

 the Rook in Europe, and a few points of comparison in their food 

 may not be without interest. The food of the Crow consists of 

 about the same proportion of animal and vegetable matter as that 

 of the Rook. 



In the first four items of Dr. Hollrung's list the Crow and the 

 Rook present a great similarity of taste, the Lachnostenia of this 



