B 



FIG. 7. THE PERIODICAL CICADA, 

 Cicada septendi r //// 



Fi<;. 9. OVIPOSITOR OF THE PERIODICAL 

 CICADA, a. DOKSAI. VIEW : h. \'KNTKAL 



VIEW 





: 



FK;. 8. ORGAN OF SONG OF^THE PERIODICAL CICADA, a. VENTRAL SIDE, 



SHOWING LIGHT-COLOURED PLATES COVERING SOUNDING DISCS; b. DORSAL 

 SIDE. SHOWING LIGHT-COLOURED TIMBALS; c. SECTION OF BASK OF ABDOMEN, 

 SHOWING ATTACHMENT OF LARGE MUSCLES TO TIMBALS; d. ENLARCiED 

 TIMBAL, NORMAL POSITION; . ENLARGED TIMBAL DRAWN IN FORCIBLY BY 

 THE ACTION OF THE MUSCLES, AS IN SINGING 



