9546 Insects. 



bv man in very many other instances, in a manner highly detrimental 

 to his own interest : he pays the price of a sack of grain for every owl 

 nailed to his barn-door, because that owl would destroy mice every 

 night ; and these mice being relieved of their oppressive enemy would, 

 in a very short time, destroy a sack of wheat, peas or beans. The 

 kestrel, in like manner, kills mice, and the death of a kestrel may fairly 

 be reckoned a loss of five pounds. A sparrowhavvk left to himself, 

 even by scaring the sparrows from the ripening grain, will save the 

 wages of at least three boys. In Scotland the incessant warfare against 

 birds of prey, and the near accomplishment of their extermination, has 

 allowed such an increase of the ring dove as to threaten, by their 

 insatiable voracity, a dearth of cereals for the food of man. Associa- 

 tions are formed, officers appointed, speeches made, rewards offered : 

 the object being solely and exclusively to remedy the evil which the 

 speech-makers have, by their supposed sagacity, induced. Fifty such 

 instances might be given, but let us take the particular instance of the 

 turnip grub. Two birds make it their special and favourite food ; 

 these are the partridge and the rook. Neither of these is favoured 

 with a place in that " gamekeeper's museum," the bole of an oak or the 

 door of a barn ; but, nevertheless, they are persecuted for sport, or 

 destroyed by poison, and, whatever the pretext for the slaughter, the 

 effect is the same. Partridges and rooks alike grace our tables — par- 

 tridges under their own name, rooks, nomine viutato, as the chief 

 ingredient of pigeon pies. 



The history of the turnip grub has only been partially narrated. 

 I will endeavour to give it briefly, but in a somewhat more connected 

 form. The first author who noticed the extent of its ravages was 

 "Ruslicus" ofGodalming, in 1832; the second, Mr. Le Keux, in the 

 'Transactions of the Entomological Society,' in 1840; and the third, 

 Mr. Curtis, in his ' Farm Insects,' in 1860. Neither of these authors 

 has observed the commencement of the evil. The grub is the offspring 

 of a moth, Agrotis Segetum, which is seen on the wing twice in the 

 yeav — first, in June ; and, secondly, in October. Of course, naturalists 

 assume that the October flight is the produce of the June flight, and 

 the June flight the descendants of the autumnal fiight; this is not so; 

 there is but one generation in the year. 



The egg is laid in June, on the ground, and soon attacks the young 

 plants of the various kinds of turnips, carrots, cabbage-plants, charlock, 

 mangold wurzel, radish, and a number of the common weeds. Having 

 tried the grub with a great variety of provender, I can vouch for its 

 feeding on any plant sufficiently succulent; but when young its 



