OF WASHINGTON, VOLUME XVII, 191.5 107 



EUURA MACGILLIVRAYI ROHWER. 



The notes on the mating of Euura macgillivrayi were made from 

 a number of males and females which issued from galls collected 

 in the type locality by Frank W. Rohwer. In this species there 

 is no real courtship, but when individuals have freshly emerged 

 and are sexually active they are more excited when in close proxim- 

 ity with an individual of opposite sex, as is evidenced by tin- 

 rapid movement of antennae and wings. There is, however, 

 very little evidence of a positive power of recognizing the opp<>-- 

 ite sex because occasionally a male would seize another male 

 or more rarely a female would seize another female. Unlike 

 certain other insects the female of this species takes as active 

 a part in looking for her mate as does the males as is proven 1 >v 

 the fact that in a number of instances a female would seize and 

 endeavor to mate with a tired male. In some few instances one 

 female mated with two different males but as far as the observa- 

 tions went no male mated more than once. During copulation 

 the wings are held close against the body or but slightly above it ; 

 the legs are spread rather far apart, the fore extending anteriorly, 

 the middle at right angles with the body and the hind distinctly 

 posteriorly. 



Copulation occupies about 65 seconds and is accomplished 

 by the two individuals facing in opposite directions. The hy- 

 popygidium of the male extends over the knob at the base of 

 the sheath, the cochlearii grasp the sides of the knob after tl it- 

 fashion of a ball and socket joint, while the preputii and penis 

 are inserted in the opening at the base of the sheath. When 

 mating is completed the female endeavors to free herself of the 

 male by using the hind legs and saw or if unsuccessful at first the 

 sheath is used. There is apparently no expansion or contraction 

 of the muscles of the stipes. After mating both sexes "dress" 

 their abdomen with their hind legs. 



PTERONIDEA VENTRALIS (SAY). 



I have never had an opportunity to observe the mating of this 

 species, and the notes here given are taken from a pair captured 

 in coitu (and remaining connected) by C. T. Greene at Plum- 

 mer's Island, Md., July 2, 1912, and from pictures taken at Plui ti- 

 mer's Island, Md., by H. S. Barber. Mr. Barber's photographs 

 are very interesting and would lead one to infer that the female 

 of this species may mate more than once and with different in- 

 dividuals. From the attitude assumed by the male in figure 

 1 of plate XXII it is evident that the male is more excitable 

 than the female. 



