4-H CLUB INSECT MANUAL 



21 



Figure 48.— 

 Ground beetle. 



one plant usually is not serious. Control of the spotted cucumber 

 beetle on most crops is difficult, but on such plants as melons damage 

 can be prevented by means of treatment with arsenicals. This insect 

 belongs to the order Coleoptera; its scientific name is Diabrotica 

 duodecimpuncta. 



Ground beetles. — Among the beetles is another family that is 

 mostly beneficial. These are the ground beetles, so named because 

 many of them have the habit of running around over 

 the ground in search of food. Most species are shiny 

 black with long legs, but a few are blue, green, or brown 

 in color. Both the adults and larvae of the ground- 

 living species hide under stones and debris during the 

 day and come out at night in search of food, which for 

 the most part consists of other insects. The beetle shown 

 here, however, is an active tree climber; it is Calosoma 

 scrutator, known as the caterpillar hunter. It is about 

 1^4 inches long. The wing covers are green with rosy 

 metallic margins. Like the other beetles, both the adults 

 and larvae have chewing mouth parts. The adults have 

 four wings, the front pair leathery and completely covering the 

 abdomen, and the hind pair clear. When at rest, the hind wings are 

 folded up under the forewings. Although it more commonly moves 

 about on foot, this beetle can fly. It overwinters as adult or pupa 

 underground. 

 Tiger beetles. — Along streams and sandy shores one often finds 

 insects about half an inch long that run very 

 rapidly, and fly to escape capture. They are 

 called tiger beetles. These beetles vary greatly in 

 color, some having brilliant metallic hues. The 

 tiger beetle shown here, Cincindela tranquebarica, 

 is about half an inch long, brownish with whitish 

 bands, and has chewing mouth parts and four 

 wings. It feeds on various small insects and other 

 small animals. It has complete life changes. 

 Both the adult and larva hibernate in holes in 

 the ground. Since this beetle feeds on other in- 

 sects, it may be considered beneficial. 



June beetles. — During the early part of the 

 summer there is an insect that flies clumsily about, 

 knocking itself against screens, lights, and the walls _ _ 

 of houses. Close examination reveals that it is a 

 rather stout, dark-brown to light-reddish colored 

 beetle, ranging from % to 1 inch in length, with 

 four wings, the fore pair leathery and the hind pair 

 clear. This insect feeds on the leaves of various 

 trees and shrubs. The larva of the June beetle is the 

 white grub that abounds in the soil, where it feeds 

 on the roots of plants. It hibernates in the ground, 

 usually lives over two full winters, and pupates late 

 in the summer. The adults emerge and lay eggs late 

 in the spring or early in the summer of the follow- 

 ing year. Cultural practices assist in the control of 

 the grubs. The June beetle shown here belongs to the order Cole- 

 optera, and is Phyllophaga drakii. 



Figuee 49. — Tiger beetle. 



Figure 50. — June 

 beetle. 



