Vol. 1.] 



Woodworth. — Wing Veins of Insects. 



123 



than that it is a vestige of the line which, in the Heteroptera, 

 separates the coriiini from the membrane. In this connection 

 a similar structure in the fossil Fvlgorina is, as already pointed 

 out, of interest. It is possible that these insects, instead of 

 representing the most primitive condition among the Rhyii- 



FIG. 59. Wings of Cicada tihicen. 



PIG. 60. Diagram of the venation 

 of Fitlgora lanternaria. The reticula- 

 tions and finer branches are omitted. 



chota, are in fact derived from an ancient ancestor resembling 

 the Heteroptera in the structure of the wings. If Eugerion 

 represents the primitive shape of head in this group of insects, 

 it is certain that the primitive shape is more nearly realized in 

 the Heteroptera than in the Homoptera, the latter standing 

 intermediate between Heteroptera and the Phytophthires. 



The front wings of the Homoptera always possess a very dis- 

 tinct clavus and are adapted 

 to the body in exactly the 

 same way as in the Heterop- 

 tera. In the Cicadidse, where 

 the wings are not elytral 

 organs, there is still to be 

 seen this adaptation in the 

 long wing-groove in the 

 notum, already described and 

 shown in Fig. 12. This is 

 certainly confirmatory of the 

 idea of the Heteropteral origin 

 of all Rhynchota. The Hom- 

 optera may, nevertheless, still retain the venation most like 

 the primitive ancestral form; for the more completely a wing 

 remains membranous, the better may one expect the venation 

 to be preserved. 



FIG. I'll. Venation of Typhlncijha conies. 



