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crops, but other cereals are also attacked, as well as lucerne, cotton, 

 peas, beans, cabbage, tomato and lettuce, in addition to many native 

 plants. The eggs of the second generation are usually laid on the 

 under-side of rubbish in the field or on Kussian thistle and occasionally 

 on different parts of the cultivated crop. The nymphs from these 

 eggs have not been observed to feed upon' cultivated crops, but live 

 upon weeds until reaching the third or fourth instar. The second 

 generation is completed about the same time that the majority of 

 grain crops are harvested, during early August. The surviving adults 

 and large nymphs of the first two generations then migrate to fields 

 of late grain, milo maize, Sudan grass, self-sown wheat, etc., or any 

 native food-plant in the vicinity. Individuals of the third generation 

 feed upon late grain crops or on native food-plants and reach maturity 

 about mid-September. Occasionally a partial fourth generation may 

 develop, though most of the nymphs do not reach maturity. In 

 October or November all adults seek hibernation quarters ; many 

 nymphs also enter hibernation but do not survive the winter. The 

 generations overlap considerably and all stages of the insect are 

 found from the middle of May until the hibernation period. There 

 is sometimes a high percentage of mortality during hibernation ; 

 the adults apparently lack the power of burrowing beneath the surface 

 of the soil and this exposes them to extreme cold and to their natural 

 enemies. 



Parasites of C. sayi include the egg-parasite, Telenomus ashmeadi, 

 Morrill, which is widely distributed through the area infested by its 

 host, and constitutes one of its most effective natural checks. The 

 short life-cycle of this species (about 20 days in the height of summer) 

 enables it to complete several generations each year and greatly 

 increases its value as a parasite. About 60 per cent, of eggs collected 

 in badly infested fields were found parasitised by this species. A 

 Tachinid, Gymnosoma fuligmosa, Desv., parasitises the adults and 

 nymphs in their last instar. The fact that the parasitised insect 

 retains its activity and powers of destructiveness up to within a short 

 time before the parasite is due to emerge, detracts somewhat from the 

 value of this fly, though its seasonal history is very similar to that of 

 its host and there are the same number of generations annually. 

 This parasite hibernates in some instances as a larva within the body 

 of its host, and probably also in the pupal stage beneath the surface 

 of the groimd. Ocypterodes eucJienor, Wlk., is a parasite of minor 

 importance, vnth a life-history and habits very similar to those of 

 G. fuliginosa. 



Predatory enemies include the Malachiid beetle, CoUops bipunctalm, 

 Say, which devours the eggs, and adults of Sinea spinipes, H.S., and 

 of Phymata erosa, Stal, which feed upon nymphs of C. sayi in the 

 field. Several species of birds and toads, as well as poultry, assist in 

 checking the numbers of this bug. 



The most effective and practical remedial measure is the destruction 

 of the adults in their winter quarters, by ploughing under or burning 

 all rubbish and weeds, particularly Russian thistle, in and abont culti- 

 vated fields. , Trap-crops, such as Russian thistle, might be sprayed 

 with a strong insecticide or chemical while the bugs are on them 

 thus destroying the weed and the insects together. Hand-picking, 

 and hopperdozers might also prove of value under special conditions. 



