INSECTS BENEFICIAL TO AGRICULTURE. 217 



The Currant-worm (Nematus ventricosus Klug). This 

 saw-fly larva or false caterpillar is far more destructive than 

 all other insects combined to currant and gooseberry shrubs, 

 since the voracious larvae appear in successive broods. 

 The female, without having paired with the male, deposits 

 her whitish cylindrical eggs along the under side of the mid- 

 ribs. In four days the worms hatch, and eight days after 

 become fully fed, burrow into the ground, remaining in 

 the pupa state about a fortnight. 



REMEDIES. Powdered hellebore or pyrethrurn mixed with four or 

 five times its bulk of cheap flour will, if constantly applied, save the 

 crop. 



INSECTS BENEFICIAL TO AGRICULTURE. 



In a great variety of ways certain insects are helpful to 

 man, and are especially efficacious either in ensuring his 

 crops or in destroying those insects which would otherwise 

 devour them. 



Fertilizers of Fruit-trees. A very important part in the 

 production of abundant crops of fruit is played by bees and 

 other honey- or nectar-gatherers, and pollen-feeding insects. 

 It is now generally acknowledged that bees, especially the 

 honey-bee, act as " marriage-priests" in the fertilization of 

 flowers, conveying pollen from flower to flower, and thus 

 ensuring the " setting" of the fruit. Orchards in which 

 bee-hives are placed bear heavier crops than those not thus 

 favored. Bees are in Europe profitably introduced into 

 peach-houses in order to effect the pollination of the flowers. 

 Many wasps, as well as butterflies and moths, species of 

 pollen-eating beetles, Thrips, and other insects, by uncon- 

 sciously bearing pollen from distant flowers, prevent too 

 close in-and-in breeding. Indeed, as Goethe said, flowers 

 and insects were made for each other. * Many plants would 



* " For it is not too much to say that if, on the one hand, flowers 

 are in many cases necessary to the existence of insects; insects, on 

 the other hand, are still more indispensable to the very existence of 



