INSECTS. 113 



year. Since a considerable time elapses between the 

 laying of the first and second batches of eggs, one 

 usually sees eggs, larvae, pupae, and beetles at the 

 same time. Entire potato fields are eaten bare by 

 the beetles and their larvae, the formation of the 

 potatoes being quite prevented. Remedies : Energetic 

 measures must be taken on the first appearance of the 

 beetle in any district. Where possible, all the beetles 

 and larvae must be collected, the plants being dug up 

 and destroyed with the beetles, pupae/ larvae, and eggs 

 adhering to them. Petroleum must then be poured 

 over the whole field and set on fire, so as to destroy 

 any insects which may be hidden in the soil. Spray- 

 ing the attacked plants with Schweinfurt green. 



The Cloudy Tortoise Beetle {Cassida nebulosa) — 

 Fig. 83. One-fifth to one-fourth of an inch long ; the 

 broad neck-shield projects in front over the small head. 

 The wing-covers, too, are much broader than the body 

 of the animal; they are longitudi- 

 nally ribbed. Dorsal side reddish- 

 brown,in young individuals greenish ; 

 always with black spots. Ventral 

 side black. Larva elongated oval, 

 yellowish green. Segments of the 

 body beset with thorn-like struc- 

 tures bearing lateral branches ; the 

 last segment possesses a " tail-fork," fig. as.— The cioudy 

 which the larva usuaUy carries bent SSL'S^f ^''"' 

 over its back and on which it heaps 

 up its dung. The beetles which have survived the 

 winter usually attack in spring only wild goose-foot 

 and orach plants, on which they lay their eggs in heaps. 

 The larvae quickly appear, and to begin with chiefly 

 keep to the under sides of the leaves. They are 

 sluggish, grow quickly, and devour the leaf substance ; 

 when fully developed they cement themselves to a leaf 

 and become pupae. In June the beetles of the second 

 generation appear, which again lay their eggs on the 



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