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the soil has been much discussed ; in these investigations they were 

 found during the winter from one to four inches below the surface, 

 except during an attack on spring oats in April and May, when they 

 were in the top inch of soil. Many larvae, particularly those of 

 Agriotes obscurus, were observed boring upwards in the stem. Migra- 

 tion to lower depths as a protection against cold did not seem to 

 occur. Larvae of Melolontha melolontha (vulgaris) were found chiefly 

 in meadows and waste land, feeding on decaying herbage, and showing 

 a definite preference for lighter soils. Lema melanopa and Sitona 

 lineata were frequently found sheltering in the stems of oat grass 

 and cocksfoot ; the attack of the latter on leguminous crops is universal. 

 The only Hymenopteron observed was an unidentified species that 

 formed galls on couch grass. 



The chief Lepidopteron was Trachea (Apamea) secalis, the cater- 

 pillars of which fed inside the base of the shoots of grasses and cereals 

 from October to the beginning of June. In February, these larvae 

 were found with those of the frit-fly {OscincUa frit) attacking winter 

 wheat ; they appear to feed indiscriminately on grasses or cereals 

 in almost any situation. Larvae of Agrotis spp. were taken feeding 

 on the roots of perennial rye grass, and were reported as attacking 

 young wheat and oats in 1918. Larvae of Triphaena pronuha were 

 taken on roots of golden oat grass ; they seem to be general feeders 

 on rye and meadow grasses. Larvae of Odonestis potaforia, which 

 feed on various grasses, were taken on cocksfoot, but were not observed 

 attacking any cereal crop. One species of Tortrix was taken on oats 

 and tall oat grass ; attempts to rear it have as yet been unsuccessful. 



The Hessian fly [Mayetiola destructor] was found exclusively on 

 cocksfoot, with the exception of one individual on couch grass. It has 

 been recorded as attacking timothy grass. This species and 0. frit 

 are frequently accompanied by larvae of Cecidomyia spp., which 

 occur in great numbers on decaying vegetation during the winter. 

 These so-called red maggots are perhaps more saprophytic than 

 parasitic in habit. 0. frit was first found in mid-November on tall 

 oat grass in a hedgerow bordering a field in which oats had been 

 severely attacked. Later, larvae were found in perennial rye grass, 

 golden oat, etc. Dipterous root feeders included Pachyrrhina im- 

 perialis, Mg., larvae of Tipida oleracea (leather-jackets) and an 

 undetermined Sciarid. P. imperialis feeds on plants in the moister 

 parts of the field, preferring rank growth near hedges ; T. oleracea 

 was very destructive to barley seedlings on newly broken-up grass 

 fields with a moist, sandy soil and with a subsoil of clay. Macro- 

 siphuni granarimn, on tall oat grass, singh' in early autumn and again 

 in summer, was the only Aphid found. Oats and hedgerow grasses 

 were attacked simultaneously. The only thrips taken was Limothrips 

 cerealium, Hal., which feeds through the winter in the larval stage 

 in hollow-stemmed grasses. 



In addition to these winter insects, almost all of which were present 

 in the summer also, there were certain species noticed only in the 

 summer. These included Amphimalhts [Rhizotrogus) solstitialis, taken 

 with larvae of Pachyrrhina imperialis feeding around the roots of 

 Italian rye grass in June, and Agromyza nigripes on wheat, oats and 

 couch grass. The moths, Odonestis Rotatoria and Arctia caja, were 

 taken feeding on grasses ; the former is a general grass feeder, pre- 

 ferring cocksfoot ; the latter frequents waste places and feeds on 

 Lamium spp., cocksfoot and other grasses, and was once observed 



