Tineidse 



(6) Prodoxus cinereus Riley. 



This species is known to breed in the flower-stems of Yucca 

 whipplei. The best way in which to set the species before the 



FIG. 261. P. cinereus. a, larva; b, head and first thoracic 

 joint ; c, anal hooks ; d, pupa ; e, pupal shell protruding from 

 stalk ; f, adult female ; g, side view of clasper of adult male. All 

 figures greatly enlarged. (After Riley, " Insect Life," Vol. V, 

 p. 306.) 



reader seems to be to reproduce, as we have done, the figure 

 given by the author of the species, in which its characteristic 

 features are carefully depicted. It is found in California. 



Genus PRONUBA Riley 



(i) Pronuba yuccasella Riley. (The Yucca Moth.) 

 No discovery in recent ydars has been more interesting to 

 students of insect and plant life than that which was made in 

 1872 by Professor Riley, of the intimate relationship which sub- 

 sists between the beautiful plants, known as Yuccas, and the 

 genus of moths to which the present species belongs. It has 

 been ascertained that the fructification of the various species of 

 Yucca is almost absolutely dependent upon the agency of the 

 female moth ; and, strangely enough, it has also been ascer- 

 tained that the pollenation of the flowers is not the result of 

 mere accidental attrition of the wings and other organs of the insect 

 when engaged in seeking for nectar in the flower and when en- 

 gaged in laying her eggs, but that she deliberately collects the 



441 



