114 



ZOOLOGY. 



leaves. In favourable weather there may be even a 

 third generation. In many it happens that the beetles 

 of the second generation migrate to beet or mangold 

 plants, sometimes damaging them to a very great 

 extent. Remedy : Rooting out species of goose-foot or 

 orach. 



The Earth Fleas, or Flea Beetles, are all small leaf 

 beetles with the power of springing, and therefore 

 provided with thick thighs. Here belong : — 



The Rape Flea Beetle {Psylliodes chrysocephalus) — 

 Fig. 84. Egg-shaped. Hind feet not inserted at the 

 ends of the shanks, but higher up. The first joint of 

 the foot is as long as the others 

 put together. The rest of the hind 

 foot is bent in a knee-like way 

 on the first long joint. Shining 

 blackish brown or blackish green, 

 rarely brownish. Larva one-fifth 

 to one-fourth of an inch, dusky 

 white ; head, neck-shield, and last 

 segment of the body blackish 

 brown. In spring and during the 

 entire summer the beetles are found 

 upon the plants of winter rape. 

 Although they gnaw the leaves and 

 the immature shoot the damage 

 caused is small. In late summer 

 or autumn the female beetles lay 

 their eggs separately at the bases 

 of the leaf-stalks of the young 

 winter rape plants. The larvte which emerge bore 

 into the leaf-stalk, and eat it completely out during 

 autumn, winter, and spring, so that the leaf dies. 

 Since the eggs are laid separately the larvse do 

 not all develop at the same time in the spring. 

 In spring many larvse eat their way from the leaf- 

 stalks into the still very short stem, which con- 

 sequently ceases to develop. It often happens that 



Fig. 84.— The Eape Flea 

 Beetle (2) with hind-leg 

 of the same ; larva (1) 

 and its head. 



