134 [June, 



out the whole course of my observations on this s|)ecies, and more 

 especially on E. livida, I have never yet seen a female in possession 

 of prey except during copulation. 



That the females of JE. opacn feed like other flics is quite certain ; 

 for large numbers of them, and of the males also, were feeding half- 

 buried in the flowers of the dandelion. E. Uvida can often be seen in 

 numbers on bramble bloom, wliile E. tessellatn and other species are 

 often abundant on UmheJliferce. 



In all some 40 individuals of both sexes with |)rey were captured : 

 34 of them were clasping various species of Bibios, 5 clasping each a 

 different species belonging to various families of Diptera, while one 

 had captured a male of its own species. In this respect E. opaca 

 affords a marked contrast with E. livida, which preys upon almost all 

 orders of Insecta, although it too chiefly attacks Dii)tera. 



Precise details of all these captures will be dealt with by Prof. 

 E. B. Poulton, F.R.S., in his next paper on " Predaceous Insects and 

 their Prey." 



My thanks are due to Prof. Poulton for much kind help and en- 

 couragement in making these observations, and to Mr. G. H. Verrall, 

 for kindly confiruiing my determination of the species. 



University Museum, Oxford : 

 3£a// nth, 1909. 



RYLEMYIA COAECTATA, Fln. : A DESTRUCTIVE WHEAT PEST. 

 BY H. F. FRYER, T.E.S. AND J. C. F. FRYER, F.E.S. 



For many years the young wheat plant in this and neighbouring 

 districts has been very extensivel}'^ injured by a Dipterous larva which 

 feeds within the stems. This larva can be found in the latter part 

 of March, and is then about I mm. to 1.5 mm. long. When full fed it 

 measures from 6 mm. to 7 mm. It ])upates in the earth at the root 

 of the plant, where it may be found in the field. When bred, the 

 perfect insect appears in June. 



The larva is more usually found in autumn-sown wheat, but in 

 1908 we observed it in " French " wlieat sown in the latter ])art of 

 February ; it seems probable, therefore, that the fly hibernates, and 

 lays its eggs in the spring; against this, however, is the fact that we 

 have never been able to find the perfect insect at that time of year. 



Economically, the difiicultyof dealing with this pest is very great, 



