EXPERIMENT STATION BULLETINS. 267 



treated, put in a similar box, were alive and lively after the lapse of two 

 weeks. Mr. Jackson wrote us some weeks afterward that this seemed to kill 

 all the beetles and did not the least harm to the foliage of the plants. Mr. 

 Davis also treated others of these chafers with pyrethro-kerosene emul- 

 sion with precisely similar results, except that the rose chafers died more 

 quickly than when treated with the kerosene emulsion only. Sludgite was 

 also tried but with no success. 



Mr. Jackson writes us that the experiment was too limited to be fully 

 satisfactory. The kerosene emulsion and the pyrethro-kerosene emulsion 

 seemed to kill the chafers, while the sludgite did no good. The foliage was 

 not injured. He adds that the rose foliage may be more able to resist injury 

 than that of the peach. We also tried the effect of both the kerosene emul- 

 sion and the pyrethro-kerosene emulsion on these chafers in the labora- 

 tory. We had but few to experiment with as the insect is not, and has 

 never been, abundant at the college. We sprayed the beetles and inclosed 

 them at once in a well ventilated box. They all died within a few hours,, 

 and those sprayed with the pyrethro-kerosene emulsion all died in even a 

 less time. As Mr. Jackson says, these experiments are too limited in both 

 numbers and extent to be satisfactory, but we have other evidence which 

 is more extensive and is right to the point. Mr. C. E. Allgeo wrote me in 

 early July, in substance as follows : I wish to thank you most heartily for 

 Bulletin No. 73. I have suffered in previous years terribly from the rose 

 bug or rose chafer. Now I know how to treat him every time. I am no 

 longer in dread of this terrible foe of the peach-grower. I made the kero- 

 sene emulsion just as you describe in Bulletin 73, using soft soap. It 

 worked just as you describe and mixed perfectly upon dilution. I sprayed 

 the trees as soon as the insects made their attack and killed all of them 

 that the emulsion struck. I have no longer any fear of this pest. Your 

 emulsion signs his death warrant. Let me add that the emulsion diluted 

 as you direct (one fifteenth kerosene), did not the least harm to the foliage 

 of the trees. We wrote to Mr. Allgeo suggesting that insects often disap- 

 pear very suddenly and queried if it might not be that they would have 

 gone any way, that possibly it was not the emulsion that killed them. He- 

 replied as follows: "You seem to be afraid that I may be mistaken in 

 some of my conclusions regarding the kerosene emulsion and rose chafer. 

 Let me say that I have too good reason to be acquainted with their habits;, 

 I know that they often come and leave very suddenly. But the experi- 

 ments were conducted with the greatest care, and I wish to reiterate, that 

 your emulsion will kill any rose bug in one half minute after it touches 

 him. It does not drive them away but kills by contact. If used diluted 

 as you direct, it will do no harm to either the fruit or foliage of the peach. 

 I observed this point very closely, and neither the leaves nor young peaches 

 were injured in the slightest degree." 



These experiments by a very cautious, intelligent peach-grower are- 

 exceedingly interesting. They agree with ours, tried both in the field and 

 laboratory, except that the beetles, with us, did not die so quickly, though 

 they did fall at once and appear dead, though life did not cease in many 

 cases for some time. Mr. Allgeo's experiments also agree with ours of 

 previous years, in that the soft soap emulsion, one fifteenth kerosene, did 

 no injury to the foliage or fruit. Prof. J. B. Smith of the New Jersey 

 experiment station reports very careful and extended experiments with 

 kerosene emulsion and pyrethro-kerosene emulsion, and states that he 

 utterly failed of success. In the face of this report, it seems to us that 



