Maevia vittata. 635 



time in the gray male , tliat tlie males, whicli as a result of this 

 association, lacked the Y-element, became the tufted males. From 

 my study, it seeras that this is really the condition of the tufted 

 male. 



It is a pleasure to express my thanks to Prof. Petrunkevitch 

 for the courtesy of his laboratory. in which the present work was 

 carried on. 



Submitted for i>nblication, 

 July, 1913. 



