FAMILY MEIX)LONTHIDiE. 75 



acorns in autumn) form at all other times the whole of their subsistence. Here, then, if my 

 data be correct, there is the enormous quantity of 480000 lbs. or 209 tons of worms, insects 

 and their larvae, destroyed by the birds of a single rookery ; and to every one who knows 

 how very destructive to vegetation are the larvse of the tribes of insects (as well as worms) 

 fed upon by rooks, some slight idea may Ije formed of the devastation which rooks are 

 the means of preventing. I have understood that in Suffolk, and in some of the southern 

 couQties, the iarvse [of insects allied to Lachnostema] are «o exceedingly abundant that 

 the crops [of grain] are almost destroyed by them, and that their ravages <lo not cease even 

 when they have attained to a winged state. Various plans have been proposed to put a 

 stop to their depredations ; but I have little doubt that their abundance is to be allribuled 

 to the scarcity of rooks, as I have somewhere seen an account that rooks in those counties 

 are not numerous. 



'A tlight of grasshoppers visited Craven, and they were so numerous as to creale con- 

 siderable alarm among the farmers : they were, however, soon relieved from their anxiety ; 

 for the rocks flocked in from all quarters by thousands and tens of thousands, and devoured 

 them so greedily that they were destroyed in a short time. 



' It was stated in a newspaper a year or two back, that there was such an enormous 

 quantity of caterpillars upon Skiddaw, that they devoured all the vegetation on the 

 mountain, and people were apprehensive that they would attiick the crops in the enclosed 

 lands ; but the rooks, having discovered them, in a very short time put a stop to their 

 ravages. 



'An extensive experiment appears to have been made, the result of -which has been the 

 opinion that farmers do wrong in destroying rooks, jays, sparrows, and indeed birds in 

 general, on their farms, particularly where there are orchards. That birds do mischief 

 occasionally, there can b6 no doubt ; but the harm they do in autumn is amply com- 

 pensated by the good they do in spring, by the destructive havoc they make among the 

 insect tribes. The quantity of grubs destroyed by rooks, and of caterpillars and their grubs 

 by the various small birds, must be annually immense. Other tribes of birds, which feed 

 on the wing, as swallows <ind martins, destroy millions of winged insects. Even some, 

 usually supposed to be so mischievous in gardens, have actually been proved only to 

 destroy those buds which contain a destructive insect. Ornithologists have of late de- 

 termined these facts to be true ; and officers would do well to consider them, before they 

 waste the public money in paying rewards to idle boys and girls for the heads of dead 

 birds, which only encourages children and other idle persons in the mischievous employ- 

 ment of fowling. On some very large farms in Devonshire, the proprietors determined, a 

 few years ago, to try the result of offering a great reward for the heads of rooks ; but the 

 Issue proved destructive to the farms, for nearly the whole of the crops failed for three 

 succeeding years, and they have since been forced to import rooks and other birds to rc-stcck 

 their farms with.^ 



