Io Bra, Food of European Birds. ee 
were evenly distributed through the twelve months of the year, 
but were all killed in a restricted area. Mr. Gilmour thinks, 
however, that the results obtained would not differ greatly if they 
had been collected over a larger district, as the one in question 
may be considered as fairly typical of southern Scotland. 
The food found in the 336 stomachs was classified under four 
heads, viz: (1) insects and grubs, (2) roots, (3) cereal grains and 
husks, (4) miscellaneous. Of these the third is of the greatest 
importance, both from its economic interest and from the fact that 
it is the food most often taken. Mr. Gilmour reckons his per- 
centages from the number of times that the bird has taken the 
food, and from this concludes that grain and husks constitute 58 
per cent of the Rook’s food.. Insects and grubs, reckoned in the 
same way, amount to 23 percent. It can hardly be claimed that 
this is the most accurate method of calculating the relative 
amounts of food found in a bird’s stomach. Birds are fond of 
eating a great many different things, the aggregate quantity of 
which may be small, just as human beings eat a little butter and 
sugar at nearly every meal, but never make a whole dinner of 
either. To illustrate, in an examination of 2258 stomachs of the 
Crow Blackbird corn amounted to 35 per cent of the food by bulk, 
but when reckoned by the number of times taken it aggregated 
52 per cent. 
Insects and grubs are mostly eaten by the Rook from May to 
August inclusive, but only in June and July do they amount to 
more than any other item. As most of the insects are said to be 
useful species, Mr. Gilmour is of the opinion that the harm done 
by their destruction ‘‘can scarcely be considered as counter- 
balanced by the grub consumpt.”” On the whole, his verdict is 
against the Rook, for he says: “Taken altogether, the Rook has 
almost no claim to agricultural regard. . . . Is not the broad fact 
clear that grain is the staple of staple foods for Rooks? Lusting 
for it as these birds do, we may rest assured that the Rook will 
attack and prey freely upon the farmer’s grain whenever and 
wherever favourable opportunity is presented; whether soft or 
hard, whether sprouted or unsprouted, whether ripe or unripe, 
whether in dung or on stubble-field, is of little moment to the 
Rook.” While he acknowledges that much of this grain was taken 
