Ill 



lected a ball of pollen which it holds on the under side of 

 the head by the maxillae. It appears like a large craw. It 

 is sometimes three times as large as the head of the insect. It 

 immediately leaves the flower to search another. It now de- 

 posits its egffs in the side of the ovary. The ovipositor con- 

 sists of four horny bristles pressed together which is well 

 adapted for boring the tissues of the ovary. After the 

 eggs are deposited the moth runs to the hollow funnel shap- 

 ed stigma, she then rolls up her proboscis-like mandibles and 

 places the pollen on the stigmas. The eggs hatch on the 

 fourth or fifth day Each larva requires from 18 to 20 seeds 

 for its develo[)ment. When mature it bites a hole through 

 the fleshy wall and reaches the ground by means of a thread, 

 enters the soil and forms an egg shaped cocoon. It remains 

 in this stage till the following summer. About fourteen days 

 before the flowering time of yucca it pupates and when the 

 flowers open, tiny moths issue from the pupa. The pollina- 

 tion of yucca is an extraordinary case. Without the yucca 

 moth the viscid pollen could not reach the stigma. If the 

 yucca moth is excluded seed will not develop. Yucca angust- 

 folia and Y. Whipplei, when grown in Europe have never de- 

 veloped a single seed. 



Dr. Riley says: "Upon a superflcial view this little 

 moth shows nothing very peculiar. The general coloration 

 is white, the primaries being purely white on the upper sur- 

 face, so that when »t rest in the half-open flowers of the 

 Yucca it is not easily detected. The under surfaces, how- 

 ever, are dusky and ofiset in flight the whiteness of the rest 

 of the body, bo as to render the species somewhat difficult 

 of detection while flitting from plant to plant. The male 

 shows no very marked peculiarities to distinguish it from the 

 other members of the family, the most noticeable being, 



