FORM AND FUNCTION 



265 



B. 



called veins or nerves. In 

 the grasshopper the struc- 

 ture and shape of the two wings on one side 

 differ very materially. (Fig. 202, w w.) 



Mesothoracic Wing. This is frequently 

 called the tegmen. It is long and narrow, 

 and heavier than the metathoracic wing. 

 (Fig. 202.) 



Metathoracic Wing. - - The metathoracic 



FIG. 202. Dorsal aspect of body (female). A, head : i, antenna ; 

 2, epicranium ; 3, compound eye. B, prothorax : a, pnescutum; 

 6, scutum ;.c, scutellum ; d, post scutellum. C, mesonotum: se, 

 scutum; scl, scutellum; to, tegmen, or wing-cover. D, mi-tano- 

 turu : ac, scutum ; scl, scutellum ; ic, wing. E, abdomen : ;, L', 3, 4, 

 5, S, 7, 8, 9, 10, 11, segments ; aw7, auditory organ ; sp, spiracles ; ,, 

 cerci ; pp, podical plates ; o, ovipositor. Enlarged about three and 

 one-half times. 



wings are Lroad and fan-like, capable <>t he- 

 ing folded in plaits, and are concealed along 

 the sides under the tegniina when not in use. 

 Since these arc relied upon for the principal 



