50 



SMITHSONIAN MISCELLANEOUS COLLECTIONS 



erally the two on each side are interlocked by dovetaiHng grooves 

 and ridges on their opposing margins (fig. 20) , so that they may freely 

 slide upon each other without being separated. Judging from the 



lYlf 2Vlf rk 



Fig. 13. — Ovipositor of adult Sciiddcria. 



A, dorsal view of base of ovipositor. 



B, ventral view^ of same. 



C, lateral view of ovipositor, with left third valvula removed near base. 

 aiv, anterior intervalvula ; b, articulation of first valvifer with second valvifer ; 



c, attachment of first valvula to first valvifer; e, apodeme of first valvifer; 

 g, apodeme of second valvifer; k, apodeme of posterior intervalvula; piv, pos- 

 terior intervalvula ; pnvl, pons valvularum ; ra, ramus of second valvula ; iVl, 

 first valvula; 2VI, second valvula; 3VI, third valvula; iVlf, first valvifer; 

 2Vlf, second valvifer. 



mechanism of the ovipositor in Sc udder ia it would appear that the 

 principal mobile elements are the ventral valvulae, which are movable 

 by the muscles of the first valvifers. 



