ECONOMIC ZOOLOGY ENTOMOLOGY. 359 



instance have they actually been obsen-ed feeding on corn roots, althougli 

 special attention has been given to their feeding habits. 



In the laboratory the eggs hatch in from 6 to 10 days, but the larvae have not 

 as yet been reared to maturity, notwithstanding repe;ited attempts to do so. In 

 numerous searches made in cornfields, wheat fields, grass, and fields grown up 

 with weeds, the larvje have not as yet been found feeding on plants other than 

 corn. The first larvai found in the field were observed at Wellington, Kans., 

 July 20, 1910, in small, round earthen cells from 4 to 6 in. deep, with a small 

 burrow leading toward the corn roots which had been more or less eaten. Very 

 few larVjB or pupte have been found in sandy or light soils, and correspondingly 

 few injured corn roots have been observed. 



Laboratory records made at Brownsville, Tex., by Vickery indicate that the 

 larval i^eriod extends from about April 1 to June 15, while the author's observa- 

 tions at Piano, Tex., show the larval period to range from April 1.5 to July 1, 

 and at Wellington, Kans., from May 1 to July 15. " In the bottom lands of the 

 Arkansas lliver, near Paris, Ark., the larvae had pupated and practically all the 

 adults had issued by July 22, 1914, indicating that they began pupating as early 

 as July 1. In the vicinity of Wellington, Kans., the larvae began to pupate about 

 the middle of July, pupae being found as early as July 20 and as late as August 

 14. The period for maturing the pupa seems to be about 15 days, although no 

 exact data have been obtained. The first pupae to be found were in earthen cells 

 in the soil near corn plants at depths of from 4 to 6 in." 



Because of the fact that the adults have the habit of dropping from their 

 food plants to the ground and hiding when disturbed, they are very rarely seen. 

 The beetles seem to prefer feeding early in the morning, late in the evening, 

 or at night, or on cloudy days. The adults issue from pupal cells about the 

 middle of July in central Arkansas and the first of August in southern Kansas, 

 emergence extending over a period of about one mouth. They do considerable 

 feeding on the kernels of unripe ears of corn and buds of cocklebur before en- 

 tering hibernation, which begins early in the fall. Corn is the only cultivated 

 crop that has been found to be attacked in sufficient numbers to cause serious 

 damage, but the beetles have been observed to attack the young leaves and grow- 

 ing shoots of cocklebur, smartweed, Japan clover, and crab grass. They have 

 also been observed to feed upon soi'ghum, Alopeciirus geniculaUis, cotton, and 

 alfalfa, but on the latter plant only in reai-ing cages in the laboratory. 



In regard to remedial measures it is stated that a great number of beetles 

 have been collected at lights, indicating that a powerful light trap located in the 

 vicinity of the infested field might materially reduce them, especially in the 

 early fall when they are flying in search of hibernating quarters. It is suggested 

 that the cleaning up of all rubbish in the cornfield early in the fall, especially in 

 fields of very late corn, will prove an effective remedy in the protection of suc- 

 ceeding crops. No remedy has been found that can be recommended in combat- 

 ing them after they once enter the cornfield. If a crop is so badly damaged as 

 to be worthless it can be replanted with safety from damage by this insect about 

 one month after the regular planting time, since within a few days after the 

 leaf-beetles have killed out the first planting they will leave the field. It Is 

 thought that something might be gained by delaying corn planting in localities 

 where beetles have been injurious the previous year. Experimental work by 

 Gibson in the vicinity of Charleston, Mo., during late April and early May indi- 

 cates that the beetles can be readily destroyed by a poison bran bait, consisting 

 of 25 lbs. of wheat bran, 1 lb. of Paris green, 1 gal. of low-grade molasses, and 

 the juice of 3 oranges, with enough water to bring the mixture to a stiff dough. 



A list of 8 references is included. 



