• WIRE-WORMS AND CLICK-BEETLES 37 



flying from pool to pool would be tp lose all that can be 

 gained by transformation. Accordingly we find that even 

 insects so eminently aquatic as Dytiscus are capable in their 

 adult state both of flight and aerial respiration. Many a young 

 collector has been startled to find that water-beetles, which 

 he left swimming about in a tank, have flown to a distance 

 before morning. 



7. WIRE-WOEMS AND CLICK-BEETLES 

 (Various species of Agriotes, especially A, lineattts) 



Wire-worms are commonly reckoned as the worst pests of 

 the farm. They feed chiefly on 

 the roots of grass, cereals, hops, 

 turnips, potatoes, and other crops, 

 and abound on sandy or gravelly 

 soils. The true wire-worms are 

 the larva of beetles, which in their 

 adult stage are called click-beetles, 

 but millipedes and leather jackets, 

 which are not beetles at all, are 

 often included under the same 

 name. Wire-worms devour roots 

 and stalks, and as they travel 

 about from plant to plant, they 

 spoil a great deal more than they 

 eat. They live three years or 

 more as larvae. It will be re- 

 membered that the larvae of the 

 chafers also go through more than 

 one season. Burrowing larvae, 

 which feed on vegetable substances 

 bulky in proportion to the nutri- 

 ment contained, are commonly 

 creatures of slow growth, the larval stage being prolonged 

 by the circumstance that during part of the year they do 

 not feed at all. It is quite otherwise with most leaf-eating 

 larvae. Here the food is both more nutritious and more 

 readily accessible, but it can only be procured during 

 the summer months. Leaf-eating larvae accordingly complete 



Fig. 2S- — The left-hand figure shows 

 the larva of Agriotes Hnea^jus. To 

 the right is shown, in two posi- 

 tions, another wire- worm (Corymbites 

 Eeneus?). All magnified. 



