336 



General Biology 



lip, called the labium, and are attached to crescent-shaped genae 

 ( ). The cheeks are called genae ( ), 



while narrow postgenae are back of these. 



The maxillae are the accessory jaws, and are composed of three 

 regions, the lacinia or maxillae proper, the gulea ( ), 



Three ocelli or simple eyes 



Compound eyes 

 Antennae 

 Clypeus (c). 



Labrurn 



Palpifer or palpus bearer 



labial palpi 



Fig. 217. 



A. and B. Skull of grasshopper; C. Melanoplus differentialis. a, Antennae, 

 c, clypeus; e, compound eye; /, front; g, gena; /, labrum; Ip, labial palpus; m, 

 mandible; mp, maxillary palpus; o, ocelli; oc, occiput; pg, post-gena; v, vertex. 

 (After Folsom.) 



C. Head and Mouth-parts of an insect. (After Tenney.) 



the middle spoon-shaped part, and the maxillary palpus, a special sense 

 organ. This palpus is in turn composed of various segments, the broad 

 basal piece being called the stipes ( ) which joins 



in turn with a smaller cardo ( ). 



The lower lip or labium is composed of two broad terminal flaps 

 called the ligula ( ). The mentum ( ) 



is the basal portion, while the small immovable submentum lies between 

 the mentum and the gula. 



v^ 



The right wing of a male mosquito, Anopheles maculipennis. A, anal area; 

 1st A, anal nervure; C, costa; Cu, cubitus; H, humeral cross-nervure; /, cross- 

 nervure between R and i? 4 + 5 ; J, cross-nervure between radial and medial sys- 

 tems; K, cross-nervure between medial and cubital systems; M, media; O, cross- 

 nervure between R x and R n ; R, radius; Sc, sub-costa. (From Sedgwick's Zoology, 

 after Nuttal and Shipley.) 



The thorax is divided into a prothorax, mesothorax and metathorax, 



easily distinguished by the three pairs of legs, one pair of which is 

 attached to each of the three thoracic divisions. The prothorax consti- 



