CHAPTER XVI 

 THE WINGS OF THE HOMOPTERA 



(a) THE MORE GENERAL FEATURES OF THE WINGS OF THE HOMOPTERA 



In the order Homoptera the two pairs of wings are usually similar in 

 texture, and each wing is practically of the same thickness throughout. 

 This is in marked contrast to the conditions in the Heteroptera, where the 

 two pairs of wings differ in structure, the basal half of the front wings being 

 thickened. It was this difference in the structure of the wings of the two 

 groups that suggested the contrasting names Homoptera and Heteroptera 

 for what were regarded until recently as two suborders of a single order, the 

 Hemiptera. 



The wings are usually membranous, but in some the front wings are 

 subcoriaceous. In these cases, however, they are of quite uniform texture 

 throughout, and not thickened at the base as in the Heteroptera. 



A striking dift'erence be- 

 tween the wings of the Hom- SeR+M+ Cu,+ lstA 

 optera and those of the 

 Heteroptera is that in the 

 Homoptera when an anal 

 furrow is developed it occu- 

 pies the usual position, that 

 is behind the cubitus, along 

 the first anal vein instead of 

 in front of the cubitus, as in 

 the Heteroptera. 



Many wingless forms 

 exist in this order; in the 

 family Coccidae the females are always wingless; and in the family Aphididas 

 the males may be either winged or wingless, while the females and certain 

 generations of the agamic forms are wingless. In the Coccidae the males 

 have only a single pair of wings, the hind wings being represented by a 

 pair of club-like hal teres. Each of these is furnished with a bristle, which 

 in all of the species that I have studied is hooked, and fits in a pocket on 

 the wing of the same side. 



If only the wings of adult Homoptera be studied, the venation of these 

 wings appear to depart widely from the hypothetical primitive type. 

 There seems to be little in common with this type in the wings of an aphid 

 (Fig. 267), of a membracid (Fig. 268), or of a cicada (Fig. 269). But in 

 each case when the trachea that precede the wing-veins are studied it is 

 easy to determine the homologies of the wing-veins. 



(269) 



Fig. 267. — The wings of an aphid (After Patch). 



