9 



enormous number of individuals, as many as 400 being found in 

 a pellet of the Black-headed Gull. The larvae or " Leather 

 Jackets " are also eaten in considerable numbers, especially by 

 Rooks, Starlings, and occasionally also by other birds (Lapwing, 

 Curlew). Beside the post-mortem records some important 

 Field Notes are also given in connection with the Rook (p. 53) 

 and the Black-headed Gull (p. 85), so that we have abundant 

 evidence that these insects are destroyed by birds in large 

 numbers and possibly to a greater extent than any other pest 

 of the farm. 



Green-bottle Flies, &c. (Muscidse, Bibionidae, &c). — These 

 insects do not appear to be eaten by birds to any great extent ; 

 but it may be interesting to note that the species, Lucilia 

 sericata, whose maggots or larvae are so harmful to sheep, 

 occurred in the stomachs of three Willow Wrens ; and there is 

 one record of the Blue-bottle Fly (Calliphora erythrocephala) 

 from the Swallow. The maggots or larval stages of these in- 

 sects were rarely found ; but there is an interesting find of the 

 larvae and pupae of the Holly Fly (Phylomyza aquifolii) in a 

 Blue Tit (No. 114). Representatives of the family Bibionidce 

 were found in a few instances, but these are of little economic 

 importance. Of the beneficial species there is but a single 

 record of the larvae of a Syrphid Fly (No. 464). 



Plant Bugs, Plant Lice, Scale Insects, &c. (Hemiptera). 



The larger members of this order, more especially the true 

 plant bugs (Gymnocerata), appear to be generally distasteful 

 to birds, as there is but one record of these insects from a Nut- 

 hatch (No. 160) taken in Gloucestershire. The predaceous 

 Water Bug or "Water Boatman" (Notonecta glauca), on the 

 other hand, has been found in several instances, though, as 

 a rule, in small numbers only. In captivity these bugs are 

 most voracious feeders, and will attack and destroy young fish 

 of various kinds when placed together in aquaria ; but whether 

 this habit obtains to the same extent in open waters is un- 

 certain. 



American Blight (Schizoneura lanigera). — Great numbers of 

 this pest were found in the Golden-crested Wren (Nos. 57, 58), 

 and this bird has also been actually seen to feed extensively 

 upon it. Enormous numbers were also found in the stomachs 



