454 THE INSECT WOELD. 



these frosts come after mild weather, they surprise the larvae at 

 the surface of the soil, and kill them. Unfortunately, the same 

 causes do harm to the plants which have already begun to spring 

 up. Nature has not then sufficiently provided the means of 

 destroying these mischievous beings. One would say that she 

 had not foreseen their extraordinary multiplication, which has 

 been, we must confess, encouraged by agriculture and by the 

 cultivation of the land. 



Animals do not contribute much towards limiting the number 

 of cockchafers, although the latter are not wanting in natural 

 enemies. Among insects, it is the large species of Carabus which 

 search after the larvae as well as the adult cockchafers. The 

 Carabus auratus attacks them with great coolness. M. Blanchard 

 saw a carabus seize a cockchafer in the middle of the road, 

 open its belly with its mandibles, and devour its intestines. 

 The cockchafer tossed about from one side to the other, and 

 even walked, while it was undergoing its cruel punishment ; and 

 the Carabus followed it without interrupting its work. Some 

 reptiles, many carnivorous animals, s'uch as the shrew-mouse, pole- 

 cats, weazels, rats, and certain birds, especially the night-birds, 

 prey upon the cockchafer and its larva. Ravens and magpies, 

 which one sees going from clod to clod, make savage but insuffi- 

 cient war against them. In fact, all these animals together do 

 not destroy the hundredth part of the cockchafers which are born 

 every year. 



As an example which will show the extent of the evil, a 

 field of 29 acres was ploughed up into 72 furrows. At the first 

 ploughing were gathered 300 larvae per furrow ; at the second, 

 250 ; at the third, 50 more ; which amounted to 600 per furrow, 

 and to 43,200 in all. Man, who is the victim of these ravages, 

 has been necessarily obliged to think of a means of destroying 

 this enemy. Many infallible means have been proposed, which 

 have, however, given no result. Prizes have been offered, but the 

 evil has not diminished. Here are a few of the processes recom- 

 mended. 



Immediately after the ploughing, you must turn into the field 

 infested by the larvae a flock of turkeys, to whom it will be a 

 great treat to devour them ; or else, you must sow in the field 



