CHAP. XVIII. FAMILIES OF ORTHOPTERA. 123 



and live In burrows in moist ground. The eggs are laid in 

 large holes excavated in their burrows. 



The Tree-crickets (Fig. 309) are of a pale greenish color; 



they are very slightly built, and 

 Fig. 309. J f , J ' . J , . ' f 



are found upon various kinds of 



plants. The females deposit 

 their eggs in slits made in some 

 tender plant by means of their 



awl-like ovipositors. The males, produce a shrilling noise by 

 elevating their anterior wings and rubbing the edges together. 

 The Field-crickets are mostly of a brownish color, and many 

 of them are entirely destitute of wings; they deposit their eggs 

 in crevices in the earth. 



KATYDIDS OR GREEN GRASSHOPPERS (Locustidse). These 

 insects (Fig. 141) are usually of a green color; their legs and 

 antennae are very long and slender, and the females are fur- 

 nished with a sword-shaped ovipositor. The eggs are depos- 

 ited in one or more rows upon 



- ,' Fig. 310. 



the leaves or twigs of trees _ 



or plants (Fig. 310). The 



males make a shrilling noise 



by means of a glassy instrument, situated at the base of the 



anterior wings. 



LOCUSTS 01? BROWN GRASSHOPPERS (Acrididai). These 

 insects have shorter and stouter legs and antennae than those 

 belonging to the two preceding Families. They are mostly of 

 a brownish color, and deposit their eggs in masses in holes 

 excavated in the earth (Fig. 39), or in logs; these holes are 

 dug by aid of the horny plates which are situated at the tip 

 of the abdomen. 



The males of a few species make a creaking noise by rub- 

 bing their hind legs against the edges of the wing-covers; 

 others produce a rattling sound, when on the wing, by rubbing 

 the upper surface of the wings against the wing-cases. 



These insects may be further divided into two Sub-families, 

 as follows: 



