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stages of its growth. The observations on the hfe-history were made 

 under laboratory and lield conditions in south-central Kansas, at an 

 altitude of approximately 1,200 feet. The studies are, however, 

 incomplete, and the records will undoubtedly vary under different 

 conditions of latitude, altitude and humidity. 



The eggs are deposited in loose, dry or shghtly moist soil, from half an 

 inch to an inch below the surface, either singh' or in clusters of up to a 

 dozen in one place. At temperatures from 80° to 90° F. the average 

 incubation period is about 10 days, while at 68° to 70° F. it is about 

 13 days. Though abnormal conditions may prolong this period, no ill 

 effects were noted in the eggs, and no infertile eggs were ever collected 

 under field conditions. Larvae hatched in June lived on an average from 

 80 to 85 days. The greatest damage in the field occurs in the autumn, 

 principally between 20th September and 15th October, when the 

 larvae work along the soft soil of the rows of newly sown or sprouting 

 wheat and destroy all the germinating powers of the grain, sometimes 

 leaving only the outer husk. They prefer slightly damp soil, and feed 

 upon the roots and seeds of many plants and grasses, and to a certain 

 extent on decaying organic matter. They become nearly mature 

 during late autumn, and pass the winter in this condition. From 

 1st November to 15th March in southern Kansas, they are very 

 inactive and feed very little. .A.fter a semi-dormant, prepupal con- 

 dition lasting 7 to 9 days the pupal stage is reached, and lasts from 

 18 to 20 days. 



The adults also feed upon wheat grains and other seeds, and may be 

 found around the bases of wheat stacks in July. An abundance of 

 rainfall checks the extent of the damage, but under conditions favour- 

 able to the pest from 10 to 50 per cent, loss of wheat may occur. 

 Adults have been collected beneath wheat shocks in fields where the 

 temperature was 100° F., but the}^ cannot survive temperatures as 

 low as — 9°F. During prolonged droughts the beetles seem to 

 disappear entirel}^ but immediately reappear after rain. Winter may 

 be passed in the adult as well as the larval stage, but the mortahty 

 of overwintering adults is great. 



Little opportunity for studying parasites occurred, but adults of 

 Perilitus eleodis, Vier., were reared from adults of E. muricatum, the 

 larvae being attacked by the fungus, Metanhizmm anisopliae, and by 

 an obscure bacterial disease, which usually ended fatally. 



Rotation of crops is one of the most important remedial factors ; 

 the maximum injury is found where the ground has been cropped 

 with wheat continuously for several j^ears, while the minimum damage 

 occurs with maize, kafhr corn, milo, and other crops requiring some 

 cultivation during the growing season. The beetles are wingless, and 

 therefore disperse slowly. Land ploughed in late autumn or early 

 spring to destroy Heliothis (Chloridea) ohsoleta (com earworm) was 

 also cleared to a large extent of false wireworms. All plants of 

 Russian thistle [Salsola kali] and other weeds or heavy growths of 

 grasses likely to shelter the beetles should be destroyed in infested 

 fields and their vicinity. Poisoned bran mash was tried as a remedy, 

 but while a few adults fed upon it, experiments with the larvae were 

 unsatisfactory and do not show any practical value. Late autumn 

 sowing of wheat seems to be successful only in very dry seasons, and 

 then the grain may be severely attacked if it has to he in the ground 

 for some time before rain falls and germination occurs. 



