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rains, remaining under the surface of the soil during the day and 

 crawling or occasionally flying at night. Moist soil is absolutely 

 essential to them, specimens in confinement having survived for a 

 year or more in wet soil. It is however unlikely that a large proportion 

 survive the winter in the field and they are not observed in any 

 numbers after February. Eggs are laid during the wet season a few 

 inches below the surface of the soil in small pockets in the tunnels 

 made by the beetle, the incubation period being about 15 days. The 

 grub feeds entirely upon decayed vegetable matter in the soil, and 

 there is no evidence that it injures plants in any way during this stage 

 of its development. Winter is passed mainly in the grub stage, though 

 larvae hatching in September and October develop very quickly and 

 may produce adults in December to February. Pupation apparently 

 occurs during late September and early October ; the adults fre- 

 quently leave the pupal skin but remain within the cell until heavy 

 rains produce favourable conditions for their emergence. The pupal 

 cells are constructed about four inches below the surface of the soil,, 

 the pupal stage occupying between 3 and 4 weeks. The most serious 

 injury is that caused to maize, the natural food of the beetles probably 

 consisting entirely of succulent grasses. Maize, kafhr-corn, wheat, 

 oats and barley have all been attacked in experimental cages." The 

 insects attack the seed as it germinates and the plant at almost any 

 stage of its growth. The young shoot from the seed is frequently 

 destroyed, so that the plant does not appear above ground. In 

 larger maize plants the beetle eats into the stalk an inch or two below 

 the soil surface, causing the centre of the plant to wither though the 

 outer leaves may still be green, and plant after plant is thus injured 

 by one insect. 



The grubs can only exist in rich, low-lying land, though the beetles 

 may range further afield and do damage on lighter soils adjacent to 

 their breeding ground. It is obvious that the presence or otherwise 

 of suitable breeding grounds determines whether the beetles can 

 increase sufficiently to constitute a serious pest. The greatest damage 

 has been recorded on land that has been under cultivation for a number 

 of years, Probably cultivation encourages the pest by making the- 

 soil easier for the grubs to penetrate ; as they are not dependent upon 

 growing plants for nourishment the lack of natural vegetation would 

 not affect them. Numerous attempts to attract the beetles to 

 poisoned bait of arsenic in sugar or treacle solutions have failed. 

 The practice of collecting the beetles by children is a slow method. 

 Unfortunately experiments with remedial measures have as yet been 

 impossible, but the follo^dng methods which apply to the breeding 

 places only, are suggested as worthy of experiment. Improved 

 drainage is likely to check the increase of the pest. Ploughing the 

 area in late summer and leaving the surface in ridges during the dry 

 season should render the land dry to a greater depth than would 

 otherwise be. the case. 



By ploughing and cross-ploughing from the beginning of October 

 and breaking up the soil as much as possible, numbers of the pupal 

 cells would be crushed and the inmates destroyed. Pigs show a 

 great partiahty for these grubs and, if kept on the breeding ground 

 as much as possible between March and September, would probably - 

 devour or destroy most of them. 



