348 



COLLEGE ZOOLOGY 



the ground (C) and transform into adults (D). Twenty dif- 

 ferent broods are known in this country, and it is possible to 

 foretell approximately when and where each swarm will appear. 

 The common cicada is the green dog-day harvest- fly, Cicada 

 tibicen. The males are provided with sound-making organs, 

 and, since these are lacking in the female, the philosopher Xen- 

 archos remarked, " Happy is the cicada, since its wife has no 

 voice." 



(3) HETEROPTERA (THE TRUE BUGS, Fig. 279). The first 

 pair of wings of the HETEROPTERA, when present, are thickened 



at the base. The jointed beak arises 

 from the front part of the head. 

 About twenty-six families are recog- 

 nized in this suborder. They in- 

 clude aquatic forms such as water- 

 boatmen (CORISID^;), back-swimmers 

 (NOTONECTID^E), giant water-bugs 

 (BELOSTOMATID^E) , water-striders (Hy- 

 DROBATID^E), and marsh-treaders (LiM- 

 NOBATID.E), and land-bugs such as the 

 assassin bugs (REDUVHD.E) , bedbugs 



FIG. 270. Order HEMIP- (ACANTHIID^), chinch-bugS (LYG,EID,E, 

 TERA. Chinch-bug, Blissus -r-.- , i /,-, \ 



leucopterus. (After Webster.) Fl g' 2 79), Squash-bugS (COREID^), and 



stink-bugs (PENTATOMID.E). The 



aquatic members of this suborder show remarkable adaptations 

 for life in the water. In many the legs are modified for swim- 

 ming, the colors of the body are such as to conceal them, and 

 the methods of obtaining oxygen while under water are extremely 

 interesting. Certain of the terrestrial species are of great 

 economic importance. The assassin bugs usually prey upon 

 obnoxious insects, including the bedbug, and are therefore 

 beneficial to man; the chinch-bug (Fig. 279) is noted for the 

 enormous damage it has done to the grain fields in the 

 Mississippi Valley ; and the squash-bugs infest squash and 

 pumpkin vines. 



