1908.] 



183 



Although 1 carefully examined every unpaired Eemale seen at post- 

 anal the number was considerable— in no instance did 1 find an 

 example with prey. 



The next observations were made on June 27th, when Mr. Gr. H. 

 Grosvenor and I visited Bagley Wood, near Oxford. At 6.40 p.m. 

 we came upon a very damp spot thickly overgrown with rushes 

 (Juncus), on which were resting many individuals of this species. 

 We decided to watch events, and soon found several pairs in cop., 

 some of which were captured ; in all cases the female was noted to 

 be in possession of the prey. In one instance we were able to watch 

 the female squeezing the prey continually, probably the better to ob- 

 tain the juices. We were not ouly enabled to confirm my previous 

 observation of a day or two before, but to add a few details unnoted 

 on that occasion. Those found at rest in cop. were closely observed, 

 and it was seen that the male hung by its anterior pair of legs to the 

 edge of a leaf or grass stem, supporting the whole weight of the 

 female and her prey ; the intermediate and posterior pairs of legs 

 were tightly clasped round the female. A few males with prey were 

 also seen settled upon the rushes, and these were carefully examined 

 in order to ascertain the manner of holding the prey. From these 

 observations we were perfectly satisfied that the prey was entirely free 

 from the proboscis, being apparently held by the intermediate and 

 posterior pairs of legs. In some cases, when the prey was rather 

 large, an anterior leg would also be used for holding it, and the male 

 Empid would then hang by one leg only. In one instance three 

 males with prey were seen within a few inches of one another ; one 

 of these was boxed, and still retained its hold upon the prey for a 

 minute or so after capture ; another male with prey under observation 

 rose to a female which was circling round quite close to it, and imme- 

 diately paired in the air in the usual way. The insects were then 

 netted as they were flying locked together. Another male, with a 

 Tortrix viridana as prey, was seen to give chase to a female, and in my 

 eagerness to secure the two I lost the female. We found no difficulty 

 in distinguishing the sexes on the wing. The females fly very evenly 

 and slowly round and round, while the flight of the male is more 

 clumsy, due probably in some measure to the fact that he is burdened 

 by the prey, which, when not too small, can be distinguished during 

 flight ; the male, furthermore, looks much browner than the female. 



Further confirmation was afforded on June 29th when 1 visited 

 " Mud Lane," just off the Cowley Eoad, Oxford ; here, at 7.18 p.m., 

 in a ditch bordering Lincoln College Cricket Ground, wex-e found a 



