OF WASHINGTON, VOLUME XVII, 1915 195 



THE MATING HABITS OF SOME SAWFLIES. 



BY S. A. ROHWER, Branch of Forest Insects, Bureau of Entomology. 



There is very little information concerning the mating habits 

 of sawflies published and it is believed that the following obser- 

 vations are worth recording. Especially is this true if the writer's 

 belief, that the value of a character cannot be properly rated until 

 its function or relation to the life cycle of the species is understood^ 

 can be considered feasible. Taxonomists of sawflies have so far 

 paid very little attention to the male genitalia, but when these 

 parts are used for taxonomic purposes it is very probable that in 

 many groups it will be found that the concavity-shape and struc- 

 ture of the cochlearium will offer valuable characters. The shape 

 and length of the penis and preputium will offer other useful 

 characters. 



The terminology of the male genitalia used in this paper is 

 that given by Hartig in "Die familien der Blattwespen und 

 Holzwespen" Berlin, 1860. 



Fig. 1. Xiphydria maculata Say. Male and female in coitu. (Drawing 



by Wm. Middleton.) 



XIPHYDRIA MACULATA SAY. 



This species emerges early in the spring and from the notes 

 available it would seem that every female mates. The notes 

 on copulation presented here are summarized from many obser- 

 vations. In no case was there any courting and mating usually 

 occurred whenever two sexually active individuals of opposite 

 sexes came in close promixity. There is a great variation in size 

 of individuals of this species but, as far as the observations went, 

 size played no part in determining whether t \vo individuals would 

 mate. 



