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distributed over the southern half of the United States. The eggs are 

 deposited in dusters in pieces of weed, crevices and clods of dirt, but 

 always near maize plants. A close search in the neighbourhood of 

 other plants has failed to reveal them, although the beetles have been 

 seen feeding on such plants at the time of oviposition. In the labora- 

 tory, incubation takes from 6 to 10 days, rarely 15 days. The newly- 

 hatched larvae are about 1 mm. long, attaining at maturity a length 

 of from G to 8 mm. Larvae have been found in the soil of maize fields 

 where Xanthiam spinostitn (cocklebur) and maize were growing together, 

 and where maize was growing alone, but in no other situation. The 

 larvae were first found in small earthen cells at a depth of 4 to 6 inches, 

 with a minute burrow leading towards the maize roots, which 

 had been more or less eaten ; the larvae retreated to safety and 

 feigned death when discovered. All the outbreaks have occurred on 

 the dark, waxy, second-bottom land which becomes very sticky in wet 

 weather and very hard in dry weather. In sandy or light soils very 

 few larvae or pupae have been found and correspondingly few injured 

 maize roots have been observed. In latitude 26° N. the larval period 

 probably extends from about 1st April to 15th June ; in lat. 33°-34° 

 it is delayed a fortnight and in lat. 37°, a further fortnight. The 

 pupae mature in about 15 days. The adults are about y\ of an 

 inch long and are more or less covered with bits of soil. They 

 are very rarely seen, owing to their habit of dropping from their 

 food-plant to the ground and hiding when disturbed. The beetles 

 mainly feed in the early morning, late evening, at night, or on cloudy 

 days. They emerge from the pupal cells about the middle of July in 

 central Arkansas and the 1st August in southern Kansas, emergence 

 extending over about a month. They feed largely on the kernels of 

 unripe ears of maize and buds of cocklebur before hibernating early 

 in the autumn. Hibernation takes place under piles of maize husks, 

 etc., in maize fields. In cotton fields the beetles were found in the 

 open, unpicked cotton-bolls and beneath piles of recently picked cotton. 

 Maize is the only crop seriously attacked ; in the early spring the 

 beetles attack very young cocklebur and early self-sown maize. Japan 

 clover, crabgrass, sorghum, Alopecurus genicnlatus, and cotton are 

 also attacked. The beetles can fly considerable distances and do not 

 necessarily hibernate in the field in which they breed. Great numbers 

 have been taken at lights and, in the early autumn, it is possible that 

 light traps would be effective against them. The cleaning up of all 

 rubbish in the maize fields early in the autumn, especially in fields 

 of late varieties, would prove an effective protection for the 

 succeeding crop. When large numbers are observed in the vicinity 

 of cotton gins, the use of the rubbish for boiler fuel, would destroy a 

 great number of the beetles. Ordinarily the beetles attack a field of 

 maize when it is very young and destroy it before the farmer becomes 

 aware of their presence. No remedy exists for controlling them once 

 they have entered a maize field. A badly damaged crop may be 

 replanted with safety about one month after the regular planting time, 

 as the beetles leave the field within a few days of destroying the first 

 planting. This, taken together with the fact that the beetles appear 

 and disappear with considerable regularity from south to north, seems 

 to indicate that something might be gained by delaying planting in 

 localities where injury has been done in the previous year. The 



