126 



FIELD ZOOLOGY. 



dition of the mouth-parts. In most species of the order 

 there is a well-developed proboscis. (Fig. 53 .) This differs 

 from the sucking beak of the hemipters structurally, 

 and it is also unlike it in the manner in which it is used. 



- — CU2 



Fig. 52, A. — ^Front wing of monarch butterfly, showing veins. C, costal; 

 SC, subcostal; R, radius; DC, discal cell; R, i, z, 3, 4, 5, branches of radius; 

 M, I, 2, 3, branches of median vein; CU, cubitus; A, anal vein. 



Fig. 52, B. — ^Hind wing of monarch butterfly, showing veins; lettering same as 

 for front wing. The scent pocket is shown on the Cu^ vein. 



The beak of the hemipter is a stiff organ, and when not in 

 use, is usually folded once sharply under the head, against 

 the thorax, by means of the hinge-like articulation just 

 where the beak joins the head. Not only is this true, 



