THE HEMIPTERA 



171 



Family Pentatomidae. This group consists of land forms, many of 

 them producing a disagreeable odor which has resulted in applying to 

 these insects the common name " stink bugs" (Fig. 162). Most of them 

 suck the sap from various plants, leaving behind the odor so often 

 noticeable on berries. Others are carnivorous, attacking caterpillars and 

 sucking their juices. Many of them are minor pests and potentially 

 important ones, and their fair size often half an inch or more in length- 

 together with considerable width, giving them a broad surface, makes 

 them fairly familiar objects. 



FIG. 162. FIG. 163. FIG. 164. 



FIG. 162. Pentatomid Bug (Euschistus) , natural size. (Original,) 

 FIG. 163. Adult Harlequin Bug (Murgantia histrionica Hahn.), slightly enlarged 



(Original.) 



FIG. 164. Eggs of Harlequin Bug, slightly enlarged. (Modified from Essig. Inj. 



and Benef. Ins. Cal.) 



The Harlequin Bug (Murgantia histrionica Hahn). This pest, 

 native to Mexico and Central America, has gradually spread northward, 

 feeding on cabbage, kale, mustard, turnip, radish and other cruciferous 

 plants, and its present northern limits are now in New Jersey and Long 

 Island, Ohio, Indiana, Wisconsin, Iowa, Nebraska, Colorado, Arizona, 

 Nevada and Washington, though the insect rarely does much injury so 

 far north. 



. The adults (Fig. 163) are about half an inch long, black or dark blue 

 with bright red or orange marks, the brilliancy of the colors making the 

 insects very noticeable and resulting in the common names "calico- 

 back," "terrapin-bug" and perhaps "fire-bug" as well. They winter in 

 the adult stage under rubbish or wherever they can find protection, 

 though in the far South they are more or less active nearly all the time 

 and there the nymphs are also present then. 



Farther north the bugs become active during the early spring and 

 attack various wild cruciferous plants and lay their eggs (Fig. 164). 

 These are usually placed in clusters of about 12, in two rows, and are 

 somewhat barrel-shaped, white, with two black rings around each, and a 

 third ring on the upper end, being both very noticeable and distinctive. 

 They hatch in from 3 to 11 days according to the temperature and the 

 nymphs suck the sap from the plants for 1 to 2 months, again according 



