io6 



THE STUDY OF INSECTS 



Family Coreid^e 



The Squash-bug Family 



This family is also a very extensive one, including many species of 

 various forms. They may be distinguished by the venation of the 

 membrane of the hemelytra. This part is furnished with many veins, 



most of which spring 

 from a cross-vein near its 

 base (Fig. 175). 



The squash-bug, An- 

 asa tristis, is a good 

 example of this great 

 family. These when full- 

 grown are brownish-black bugs, with some yellow spots along 

 the edges of the abdomen (Fig. 176), and are dirty yellow on 

 the under side. This bug winters in the adult state, and takes the first 

 opportunity in the spring to lay its eggs on the leaves of squash and 

 pumpkin vines. As soon as they hatch, the young bugs attack the vines 

 and are apt to destroy them entirely. 



FlG. 175. — Hemelytron of Leptocoris Irivillalus. 



Fig. 176. — Anasa 

 iristis. 



Family Pentatomid^e 



The Stink-bug Family 



This is a family the taste and odor of which most of us know to our 

 sorrow. We learn the flavor in one experience, and conclude that once is 

 enough for a lifetime. 



It should not be concluded, however, that only members of this 

 family possess this disagreeable odor; for most of the Hemiptera protect 

 themselves by rendering their bodies unpalatable in this way. 



This nauseous odor is caused by a fluid which is excreted through 

 two openings, one on each side of the under side of the body near the 

 middle coxas. 



In this family the antennae are five-jointed; the scutel- 

 lum, although large, is usually less than half as long as the 

 abdomen (Fig. 177). 



Some species of this family feed upon other insects, and 

 so are very helpful to the farmer, one species especially 

 {Perillus bioculatus) being a gallant fighter against the 

 potato-beetle. Other species feed entirely upon vegeta- 

 fig. 177— a bles, while others live upon both vegetable and animal 



pentatomid. matter . 



The harlequin cabbage-bug or calico-back, Murgdntia histrionica, 

 is very destructive to cabbages, radishes, and turnips in the southern 

 states and on the Pacific coast. It is black with bands, stripes, and 

 margins of red or orange or yellow. The full-grown bugs live through 

 the winter, and in the early spring each female lays on the under surface 

 of the young leaves about twelve eggs in two parallel rows. The young 

 bugs are pale green, with black spots. They mature in a few days, so 

 there are many generations in one season. 



