222 



constautly arriviug, iind whatever is left by the first lot is sure to be 

 found by the second or third or some other of the twenty or more armies 

 that make their appearance day by day. 



To try the effect of repellants I used carbolated lime on a row of vines, 

 putting it on very thoroughly with a Leggett " gun." The stuff was 

 certainly repugnant enough to all but rosebngs, and they did not mind 

 it in the least. Fresh air-slacked lime dusted into the vines proved 

 equally ineffective in other hands, and whitewashing, or what practi- 

 cally amounted to it, was equally bare of results in Colonel Pearson's 

 experience. This was to be expected, where the Bordeaux mixture 

 itself was eaten. Copper evidently added nothing to the lime, and 

 ueither did the carbolic acid. I had some hope of naphthalin, and 

 dusted a row with the powdered substance, mixed with precipitated 

 carbonate of lime in equal parts. The odor was plainly perceptible for 

 10 feet either side of the row, and yet the beetles minded it not in the 

 least. They ate the leaves less, but to the buds and flowers the powder 

 formed only an agreeable relish. 



I tried it with tobacco with equally barren results. I put on the 

 tobacco powder dry, and the insects seemed to take it greedily. X. O. 

 dust was equally ineffective. Then I got up early in the morning and 

 dusted a couple of rows while yet everything was wet with dew. The 

 result was the same. Tobacco evidently agrees with this si)ecies and 

 forms only an appetizer. But I tried it again. I made a decoction of 

 1 pound of ground tobacco to 1 gallon of water, using 2 quarts of boil- 

 ing hot water and pouring through the tobacco and adding two quarts 

 of cold water. Then I stirred in the dust itself and si)rayed on a row 

 of blackberries. I selected these because the beetles were very numer- 

 ous and easy to reach. The leaves and blossoms were coated with tbe 

 brown mixture, which soon became viscid by evaporation and ought to 

 have been repugnant to all well regulated insects. But the rosebngs 

 did not mind it in the least and seemed to feed with increased relish. 

 Tobacco was evidentl}^ no good. Pyrethrum had been highly recom- 

 mended, and I gave this also a good trial. I used it first at the rate of 

 1 ounce to 1 gallon on blackberry bushes. A few of the beetles droi)ped, 

 kicked about for a few minutes until dry, and then flew back to the 

 plants and resumed their feeding, apparently none the worse. I jumped 

 from this to one-fourth pound to 1 gallon of water, using a fresh article 

 both of the Persian powder and of the Buhach in two different experi- 

 ments, stirring in the powder after extracting with boiling hot water. 

 This promised well. A few minutes after the application the beetles 

 were dropping from the plants in every direction, and in ten minutes 

 scarcely a beetle was left on the bushes. They lay on the ground, 

 struggling at first and then quiet and motionless. They were, however, 

 still alive, and I waited patiently for their death. But they had not 

 the slightest intention of obliging me, and at the end of half an hour 

 began to recover from their stupor. From a feeble motion, as though 



