258 THE SCOTTISH NATURALIST 



23-9 per cent, of injurious insects. Dr Collinge's very reason- 

 able opinion regarding the bird is that " any policy of exter- 

 mination or even general destruction would, in my opinion, 

 be a most short-sighted and unwise one on the part of agri- 

 culturists ; at the same time reasonable repressive measures 

 are very desirable, for so long as Rooks are as numerous as 

 at present, they will continue to be a source of considerable 

 harm to cereal and root crops." And, of course, we would add 

 in fairness, they will remain, even in their present numbers, 

 a source of very great good to the farmer ; especially in these 

 days when new areas of cultivation have opened the way for 

 new hordes of wire-worms and "leather-jackets." 



The position of the Missel- thrush appears also to be one 

 of some difficulty. Dr Collinge formerly considered, on the 

 evidence of twelve specimens, that it was more destructive 

 than beneficial, but further numbers have given more trust- 

 worthy information, and he now considers, and the point is 

 made very clear in his diagram of food percentages, that 

 "the bird must at present be regarded on the whole as 

 beneficial." That judgment is probably to be accepted for 

 the whole of Scotland, for in no area known to the writer is 

 the Missel-thrush "locally too common," as it appears to be 

 in the fruit-orchards of the south. 



One important improvement in method is suggested 

 by a perusal of this interesting and useful paper : it is 

 indicated by the distinctions between the agricultural and 

 the fruit-garden Sparrow, the agricultural and the orchard 

 Missel-thrush, the Skylark of the north and that of the 

 southern wheat-growing regions, and it is clearly pointed 

 to as well by the well-known diversities in the food habits of 

 birds in different areas it is that the section of country 

 covered by any one study of the food of birds should be 

 limited in area, and that its limitations, if possible, should be 

 determined by its distinctive agricultural, horticultural, or 

 natural aspect. Only when the farmer in any particular 

 locality begins to see that the statistics of the laboratory 

 have some close relation to the facts which force themselves 

 upon his notice throughout the year, will he begin to put 

 faith in the conclusions drawn from necrological surveys. 



