io8 



INSECTS 



In the family Lampyrida, containing the fire-flies 

 and soldier beetles, and among the flower beetles of 

 the families Malachidcs and Cleridce, we have a series 

 of species of which a large number are predatory in 

 the larval stages, while the adults are feeders on pollen 

 or vegetable tissue. Among the fire-flies some of the 

 larvae are feeders on snails, while others, with those 

 of the soldier beetles, are limited to an insect diet. 

 They are largely found on the surface of the ground 

 or just beneath it, and they get a great many of the 

 plant-feeding forms that go underground to pupate. 



Withal they are rather gen- 

 eral feeders and not specific 

 checks. Among the Clerida 

 the majority of the species 

 are predatory on wood-boring 

 forms, and some of them are 

 specific checks on the bark- 

 boring Scolytids. The larvae 

 are elongate, rather slender 

 and flattened creatures with 



a large head and prominent jaws, and they enter 

 into and follow the galleries of their prey, which is un- 

 able to escape and absolutely incapable of resistance. 

 Under normal conditions these species are capable 

 of dealing with a large percentage of the wood-borers; 

 but it seems rather easy to turn the scale against them, 

 and the Scolytids often do a great deal of injury when 

 favored by careless forest practice, fire injury or other 

 checks to tree development. Taken as a whole the pred- 

 atory and semiparasitic forms among the beetles are 

 a very important factor in keeping down plant-feeding 

 forms and in preventing the undue increase of other 

 species which are not directly harmful and may even 

 be beneficial. 



FIG. 50. A soldier beetle and 

 its larva. 



