THE INSECT WORLD. 163 



A very curious series is the Corimelcemdce, or "negro-bugs," 

 distinct by their usually small size, their intense black colors, 

 which occasionally have a bluish or greenish 

 tinge, and by their very convex form. The ^"^- ^^5- 

 scutellum covers nearly the entire upper surface 

 of the body, and the insects are quite generally 

 mistaken for small beetles. They may be found 

 on plants of all kinds and sometimes in consider- 

 able numbers, but noticeable injury is rarely in- 

 flicted. Their most disagreeable habit is laying Fiea-uke negro- 

 eggs on a number of the small fruits, like black- ."f.' onmc ana 



o* _ ' /)M/jca>-ia, enlarged. 



berry and raspberry, and if these are crushed 



in eating, an excessively disagreeable, "bed-buggy" taste is 



noticed. 



The last family of this order to which we call attention, even 

 though it is not injurious, is the Scutelleridce , the species of 

 which are yet more oval, though perhaps less convex than the 

 preceding. As before, the scutellum covers nearly the whole 

 of the abdomen, but these species are often brightly colored. 

 They are moderate in size or quite large, and are southern and 

 western, a few species only being rarely found northward. 



Taking it altogether we have in the heteropterous series of the 

 Hemiptera forms which gain their food by sucking juices, and in 

 perhaps the majority of instances the juices of plants. Yet, 

 taking it altogether, there are comparatively few seriously injuri- 

 ous species, and, if we except the " chinch-bug," they do not 

 begin to compare with their homopterous brethren in the amount 

 of injury they do to farm crops. The insects are nearly all diffi- 

 cult to deal with, as they resist insecticides quite strongly. No 

 weak mixtures affect them, and even the kerosene emulsion 

 cannot be diluted more than three or four times, if any large 

 proportion of adults are to be killed. Stomach poisons are out 

 of the question, of course, and we are thus reduced to mechani- 

 cal means or farm practice to avoid trouble. These methods 

 have been indicated in the course of the chapter, and need no 

 formal repetition. 



