40 



GRASSHOPPERS IN GENERAL. 



FIG. 12. (Original.) Front view 

 of head, with clypeus and labrum 

 removed to show mandibles in 

 position, a, antenna; 6, ocelli; 

 /?, compound eye; <', mandible; 

 d, maxilla ; e, maxillary palpus ; 

 /, labium ; g, labial palpus. En- 

 larged about five times. 



sclerite is a horny substance called chitine 

 An examination of the body wall shows it 

 to be composed of a number of distinct 

 pieces, or sclerites; the lines separating 

 these pieces are knowii as sutures. Su- 

 tures here, just as in the anatomy of the 

 human skull, are not freely movable joints. 

 The term, "joint," is reserved for those 

 articulalations where free motion is per- 

 mitted, as is the case at the connections of 

 the parts of the locust's leg. 



An examinination of the whole body 

 will readily show three divisions the 

 head, thorax, and abdomen. The head, 

 apparently one piece, contains the mouth, 

 eyes, and the long horns, knowii as an- 

 tennaB the thorax is the heavy central part 

 of the body, furnishing attachments for the 



wings and legs; the abdomen is the slender 



portion extending backward from the base of 



hind wings. 



The head. The accompanying figures show 



the head with mouth closed (fig. 12), but upper 



lip, labrum, removed to reveal comparative size 



of jaws and head. Fig. 13, with mouth open, 



illustrates the tongue, hypopharynx in the 



center, mandibles, and part of the maxillae on 



each side beneath mandibles. With such 

 tools and the power to use them, is it to be 

 wondered that this insect is. omnivorous. 



The compound eyes, one on each side of 

 the head, are the most conspicuous divi- 

 sions of the head. Their surface is made 

 up of a large number of hexagonal plates. 

 Each of these plates forms the surface cov- 

 ering for a simple eye admitting but one 

 ray of light. The compound eye is but a 

 collection of these simple eyes. 



The simple eyes. Just above the base 

 of each antenna can Jbe found a small 

 simple eye; between the bases of thehorn- 

 like antenna? is another simple eye. 



The many jointed antenna extend from 



FIG. 16. (Original.) Cly- 

 peus and labrum. Enlarged 

 about five times. 



of ^adf'wSh'mandibfe? spread 

 ESS?/ 



