148 



Note on an Aquatic Hymenopterous Insect. 



By W. Burton. 



(Read May 17th, 1895.) 



On looking over some weeds collected from a small pond at 

 Totteridge, on the occasion of onr last excursion, I saw a small 

 fly threading its way amongst a tangled mass of conferva and 

 rootlets at the bottom of a small stage tank. Thinking it strange 

 that, although seemingly out of its proper element, it did not 

 seem in any way distressed, I continued my observations. Shortly, 

 on coming to a small open space in the water, I saw it very 

 deliberately spread its tiny wings and fly. I say fly advisedly, for 

 it was certainly more like flying than swimming. This enabled 

 me to see that it bore some resemblance to the fairy flies 

 (Mymaridse), possessing, as usual with them, a pair of anterior 

 club or battledore shaped wings, exquisitely fringed and covered 

 with hairs, as were also the posterior, which are simply narrow 

 bands, and also the slender waist and pointed extremity common 

 to the Iclmeumonidse. I at once isolated it, and consulted our 

 mutual friend, Mr. Fred. Enock, who at once identified it as the 

 same form found by Sir John Lubbock, at Chiselhurst, in 1863, 

 and described and figured by him in the Transactions of the 

 Linnean Society in 1864 as Polyncma natans, and which has 

 rarely been found since. I am unfortunately not able to give you 

 a scientific account of this find, as my entomological education 

 has been somewhat neglected, but thought it my duty to bring it 

 under the notice of our Club, as it was unearthed at one of our 

 excursions, and in hopes that it might interest some of our 

 members who are conversant with this form of insect life. I may 

 mention that Mr. Enock and myself visited the pond on several 

 occasions since, and have succeeded in obtaining many more speci- 

 mens, both male and female, which he is now keeping under obser- 

 vation with the view of publishing the results later on. 



