122 University of California Publications. [Entomology 



line, becoming attached at both ends to the veins of the 

 corium. From this accessory membrane-vein the discontinu- 

 ous independents, having reestablished themselves, proceed to 

 the margin. 



The hind wings are unlike anything in other orders. The 

 venation is simple and not particularly difficult to interpret- 

 The primary is strong and on or near the margin. A little 

 beyond the middle it makes a bend and is thickened or gives 

 off a spur-like branch toward the tip. Just l)ehind this line 

 there is a wrinkle corresponding to the anterior longitudinal line 

 of the front wing. There are two independents fused together 

 at the middle, and connected to the primary by a cross vein 

 in most cases. The posterior of these two independents unites 

 at the tip with an accessory vein along the first fold. Between 

 this fold and the next there are two of these accessory veins, 

 which unite with each other toward the base, and are some- 

 times connected by a cross vein. Still behind this is a forked 

 first posterior and, finally, a single second posterior. 



Redtenbacher is the only one who has attempted to trace 

 the homologies of the veins in this group, and I differ from 

 him here, as in Orthoptera, and for the same reason. He 

 believes that the vein VII should lie before the anal field in 

 the front wings. The basal attachments of the veins show 

 that his interpretation is not correct. 



HOMOPTERA. 



If one excludes the Phytophthires, this group becomes fairly 

 uniform in the character of its venation. The front wings 

 vary from a condition in which both pairs of wings are equally 

 transparent, as in Cicada, to one in which they are leathery 

 and nearly opaque: but never to a stage where the course of 

 the veins can not be made out with certainty. There is much 

 difference between the venations of the two pairs of wings, 

 making it difficult at times to homologize the veins. 



The family Cicadidse forms the most distinct group of the 

 Homoptera. The venation is shown in Fig. 59. The most 

 curious feature of this venation is a mark (dotted line, Fig. 59) 

 extending across the wing, which can be seen only in certain 

 lights upon the membrane: but wherever this line crosses a 

 vein, it is very evident, because the vein is here entirely inter- 

 rupted. There seems to be no other explanation of this line 



