1897.] 50 



Also Antkocoris sylvestris, Lyctocoris campestris, and Rhyparochromus chiragra 

 (Hem.-Heteropt.). 



I took a iew Diptera, but I hope to obtain many more in tbe early 

 summer from the old nests which I have preserved. 



As I was very successful in finding Metcecus, I devote a special 

 paragraph to it. 



I got 49 out of 41 nests. Only a dozen nests, however, contained 

 it:— August 1st, 12; 4th, 2; 10th, 8; 15th, 2; 22nd, 2 ; 23rd, 2 ; 

 31st, 1 ; September 1st, 7 ; 7th, 4 ; Sth, 4 ; I4th, 4 ; 17th, 1. Several 

 nests examined after this date showed signs of the parasite, but it had 

 departed, as this wasp {V. vuJr/r/ris) was very early in 1896. 



I consider the period given the best for this work, but in a late 

 season 1 have taken Metcecua as late as October 2nd. 



The following table shows the different results of other years : — 



From this it may be inferred that any one attempting this work 

 must have plenty of leisure, and be prepared to undergo much labour. 

 He should know, or be told of, every nest (say) within a mile radius of 

 his house. (I give a small reward for the discovery of each wasp's nest, 

 provided it has not been tampered with.) He should be able to tell 

 at a glance, by the flight and manner of the wasps, whether they are 

 of the right kind, viz., V. vulc/aris (the small "anchor-faced" wasp), 

 and to form an opinion, by the number of workers going in and out, of 

 the proper time to take the nest ; and also, of course, to take it properly, 

 and bring it home intact for examination after digging it out. 



The nests in banks with rough herbage, or inside, and by the edge 

 of woods, are the most productive, and certain banks facing south often 

 contain the host and parasite year after year. The nests in open fields 

 rarely yield anything. A nest of V. germanica, although close by, 

 never contains the parasite, which I have taken in tree-stumps, and 

 once in a hot-bed in a walled garden (August Ist, September 7th). 



The parasite is reared either \n the male or worker cells, generally 

 near the edge or quite in the centre, and it is very often impossible to 

 tell without tearing away the lid, whether the cell contains a wasp or 

 parasite, which, when liberated, rushes quickly out, and often takes to 

 flight. 



