The Life-History and Anatomy of Moths 



The fore and hind wings in some of the primitive forms are 

 not connected with each other in the operation of flight. In the 

 Hepialidce there is a lobe near the base of the primaries which is 



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FIG. 12. Diagram of Wings of a Moth. (After Hampson's "Moths of 

 India," Vol. I., with modifications.) 



A. FORE WING. B. HIND WING. 



c.m. Costal margin. c.n. Costal nervure, vein 1 2 of fore wing, 



a.m. Outer margin. 8 of hind wing. 



i.m. Inner margin. s.n. Subcostal nervure. 



a. a. Apex. tn.n. Median nervure. 



i.a. Inner angle. ia,b,c. Three branches of internal nervure. 



c. Discoidal cell. 2,3,4. Three branches of median nervure. 



d. Discocellulars. 5. Lower radial. 



ar. Areole. 6. Upper radial 



f. Frenulum. 7,8,9,10,11. Five subcostal branches of fore wing. 

 7. Subcostal nervure of hind wing. 



known as thejugum, but it does not appear to serve the practical 

 functions of a yoke. This is illustrated in Figure 13. In the vast 

 majority of cases a connection between the fore and hind wings 

 is made by means of the frenulum on the hind wing, which hooks 

 into the retinaculum upon the fore wing, as illustrated in Figure 14. 

 The form of the frenulum is of use in determining the sex of 

 specimens, as in the case of the males it consists of a single 

 curved, hook-like projection, whereas in the case of the females 

 it is split up into a number of bristles. However, in some 



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