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on winter oats, winter and spring wheat, barley, rye and grasses have 

 been recorded. Infestation is most common (or most noticeable) on 

 the young plants not far advanced in growth, but the larvae of the 

 third brood will feed in the panicles of oats still hidden in the sheath ; 

 this also occurs, but more rarely in the British Isles, in the ears of 

 barley, while only two records have been traced of larvae living in 

 the ears of wheat. It has been stated that the females of the second 

 brood will only oviposit on the blossoming oats, and failing these, 

 on wild grasses. When able to choose between oats and barley, 

 the flies prefer the oats, the same preference having been noticed in 

 the case of oats and wheat. On the Continent the larvae appear to 

 winter mainly in rye, but also in winter wheat and wild grasses ; as 

 regards England little is known, but the larvae have been found in 

 winter wheat, winter oats, rye and in wild grasses, rye-grass, Arena 

 flavescens and Arrhenatherum avenaceum. Winter- wheat has also been 

 known to be attacked in the spring, the flies emerging at the end of 

 Jime and beginning of July. 



The majority of writers agree that there are three broods, though 

 it has been thought that there may be four or even five in south Russia. 

 It has been suggested that there may be a constant succession of broods 

 dependent on the state of food-plants and the weather. Probably 

 the broods more and more overlap as the season advances. The 

 period of maximum emergence of the first brood of flies in England 

 is from the middle of April to the middle of May, while that of the 

 second brood is during July. The third brood has its maximum 

 emergence in August and September, but in the case of wheat sown 

 after rye-grass or Itahan rye-grass the crop has been known to be 

 attacked even when sown as late as November or early December, 

 apparently indicating the possible migration of larvae from ploughed-in 

 rye-grass to the young wheat plants. 



In autunm and spring the eggs are laid on the leaves of the young 

 plants, preferably on the under-side, or on the stem close to the ground. 

 In the summer they may be laid on the sheaths enclosing the ears, 

 on the panicles of oats, on the young grains of oats and barley, or on 

 wild grasses. The maximum number of eggs laid in one day is 6 ; 

 in moist air and a high temperature these may hatch in 3 days, but 

 dry air will kill them. Normally only one larva is present in each 

 shoot, but as many as ten have been found in a single plant. The 

 spring and autumn larvae five in the young stem eating the tender 

 central leaves and shoot, which is ultimately killed, the plant mean- 

 while producing side-shoots. The summer larvae hve in the summit 

 of the stem, feeding on the hidden ears or panicles, or in the stems of 

 grasses. The spring and autunm larvae pupate under the sheath of 

 the outer leaves, the summer ones among the leaves surrounding 

 the hidden ear or panicle, or in the grain itself, or between the grain 

 and the husk. The pupal stage may last 8-14 days, the length of 

 time being governed by the amount of moisture, the drier the 

 conditions the longer the period. Experiments have proved that 

 flies were capable of getting through 7-9 inches of rammed wet earth 

 upon emergence from pupae buried at that depth. Very varying 

 accounts of the length of hfe of the adults have been given by various 

 writers, that of the male being from 1 day to 1 month, that of the female 

 from 2 weeks to 5 months. 



