130 liKI'Olil' OF STATK GKOI.OGIST. 



the (lolicate vit;il or<i";iiis witliiii. and also in I'lirmiii;:' a framework 

 to wliich the imisclcs of inoxciiiciil may he attadicd. lietween the 

 joints the cuticle is drvoid of chiliii and is tliin. d(di(al(\ and flexi- 

 ble, thus allowing the nt-eessary frecMlom of motion. 



The adults of insects, and in most (■a>('s. the yoiiiii;-. have six true 

 legs, and the former usually, lliouizh not alway.-, have \vin,i;'s. More- 

 over, insects breathe by a system of lubes called triicbe*, which 

 branch and ramifv tbrouidi every ])ortiiin of the body, and which open 

 externally in about ten phices on iMcb sidr of the body, instead of at 

 the front end. A locust could, tbci'cfoi'c, be ludd with its head be- 

 neath the water for an hour, without drowning:- it. In the true in- 

 sects, the Tings of the body arc ^groupcd iii three regions: the head, 

 the thorax, and the abdonieii. in uuiei'al, it may be said that the 

 head contains or bc;irs the or^ians (d' sense and of prehension and 

 mastication of the food: the thora\ tlu' oryaiis of locomotion; and 

 the abdomen tliose of reproduct ion. 



The Head. 



The head of the locust is comjiosed of four or more segments or 

 rings, solidly fused logetlier into a c;ipsule or hard box of chitin, 

 known as the ^'r/iirrnniiiiii," wliich contains the brain and associated 

 ganglia, and the mouth. Jt bears oi- gi\('s support to the antennae, 

 mouth parts, eyi's and ocelli; also intei'nally to the muscles moving 

 the nuindil)les or jaws. The broad basal portion of the t'pieranium 

 back of the eyes is known as the ••occiput:" the narrower portion be- 



■liie 

 ant/ei f T ' '-■ "V \t 



./.. \ \\ ---■-i\-r" ■ 



fCAa \ ) / // 



Ur Xv-J It"- 



7r>x 



<i 

 Fig. 3. (lO Front view of tho head of » lociut 



(b) Lateral view of the head of a locuet. 

 (After Lugger I 



tween the eyes, the "vertex," wliil.- the long frontal portion as far 

 down as the prominent transverse -uture is the "•front" or ""face." 



