INSECT NOTES FOR I912. 461 



''Abdomen above and beneath of nine segments, the first very narrow, 

 distinctly visible above, beneath visible only at the sides; second slightly 

 broader, beneath nearly entirely concealed. The remaining segments 

 are distinctly visible both above and beneath, the distal angles being 

 slightly prominent, giving the sides of the abdomen a dentate appear- 

 ance." (Horn 1872). 



"Imago. Robust, color piceous to brown, elytra often paler, surface 

 moderately pubescent. Head and thorax very convex, the mouth infe- 

 rior, mandibles broad and chisel-shaped at tip ; surface of head and 

 thorax densely and coarsely punctate ; striae of elytra deep, punctate, 

 interspaces nearly flat, rugose, and punctulate, antennae and feet rufous. 



"Length 7-9 mm." (Forbes, 1894). Fig. 498. 

 In Insect Notes for 191 1 (p. 229, Bui. 195, Me. Agr. Exp. 

 Sta.) there was published an account of experiments made at 

 Highmoor Farm, Monmouth, Maine, upon wire worm exter- 

 mination. Both poisons and repehants were used without 

 avail in the field, and as a check several wire wor-ms were 

 placed in a small jar with so-mie grains with which special pains 

 were taken to coat them heavily with arsenate of lead. Several 

 days later, so'me larvae were seen, each hal^f burled within the 

 grain, the hull intact except for a small hole the . diameter of 

 the insect's body. A month later only the hulls of the grain 

 remained. All the wire worms were still alive and apparently 

 healthy. (Fig. 497.) Tobacco dust, lime and other repellants 

 also proved ineffectual. The successful growth of Canada field 

 peas in some of the infested plots gave the suggestion that crop 

 rotation would be the solution of the wire worm problem and 

 to that end potatoes, clover, beans, oats, corn, Canada field 

 peas, and a mixture of peas and oats were sown in plots 200 feet 

 in length, but of. varying width, separated from each other by 

 fallow areas 8 to 10 feet wide. A narrow strip plowed 6 times 

 during the month of August 191 1 was crossed at right angles 

 by the 1912 plots. Owing to the very late spring and wet 

 fields, the planting was unusually late. No fertilizer was put 

 upon the field. About the middle of August the crops were 

 inspected. Making allowance for the lateness of planting and 

 lack of fertilizer, all the crops with the exception of the corn 

 were in as good a condition as could be expected. The corn 

 was rather poor though much better than on the same field the 

 preceding season. 



In preparing the field for planting half of each plot was 

 plowed in June, the other half being only harrowed. Wire 



