OUTLINES OF ENTOMOLOGY. 121 



live and reproductive systems ; strong of wing and assisted in flight by 

 numerous buoyant air sacs all these traits conspire to make it the ter- 

 rible engine of destruction which history shows it to have been. In- 

 significant individually, but mighty collectively, locusts fall upon a 

 country like a plague or blight." 



The winged locusts do not generally appear in swarms until late in 

 summer, when, after devouring all sorts of vegetation, the females fill 

 the ground with their eggs and then die. 



The young locusts, which hatch in the spring, are at hand to take 

 the next crop, and unless vigorous and combined effort is made to sub- 

 due them, by repeated plowings, they take all the early vegetation of 

 the second year. Those that survive to attain their wings return in 

 small swarms to their native breeding places. 



The species of (Edipoda often have the hind wings brightly colored 

 and prettily banded or bordered. The small species, termed Grouse 

 Locusts, genus Tettix, are characterized by the prolongation of the col- 

 lar backward so as to almost entirely cover the top of the abdomen and 

 taking the place of the upper wings, which, being useless, are reduced 

 to very small pads. In these insects the hind legs, though not long, 

 are very stout. They are of dull black or dark colors, and are usually 

 found along water-courses or in other damp places. None of the 

 species are especially injurious. 



CHAPTER XXX. 



Order ORTHOPTERA. Sections AMBULATORIA, RAPTORIA, 



and CURSORIA. 



WALKING STICKS, MANTES AND COCKROACHES. 



The " Walking sticks," " Walking leaves," and so forth, included in 

 the family PHASMIDJE, are mainly tropical species, exhibiting in their 

 forms the most exact and remarkable resemblances to twigs and leaves 

 that have been observed in nature. These imitations of inanimate ob- 

 jects are the sole reliance of these insects for safety, as they have no 

 means of defense agianst their enemies, and their movements are too 

 sluggish to permit them to escape. The Walking sticks, of which a 

 few species occur in the United States, are long, slender and cylindri- 

 cal in form, with long legs, the middle pair having the thighs somewhat 

 thickened. When at rest the front legs are pressed close together and 



