REPORT OF THE ENTOMOLOGIST. 245 



infested tree were sprayed with tlie same at night; none ascended the 

 tree, and by the next noon four dozen were dead and dying. Tests on 

 email groups gave analogous results. 



This solution poured around the bases of trees had no influence m 

 retarding the pupoe, which marched over it unaffected and ascended tin.' 

 trees. 



CarhoUc acid (1 per cent, solution) around trees also gave no result 

 C;f the pupse sprayed with this weak solution one-third were prevented 

 from molting and died. 



Acetic acid (15 per cent, solution). — The results from this are very 

 similar to those of carbolic acid of 2 per cent, strength. Applied in 

 the evening on a group of pupae, the next day eight were active, six 

 were half-molted and dying, three had emerged. Of the latter one was 

 dead and covered by a swarm of small yellow ants. On other small 

 lots the effects were similar ; nearly all eventually died. 



Acetic acid (10 per cent, solution). — This sprayed on four small lots of 

 pupae prevented over one-half from emerging. 



Alcohol (30 per cent, solution). — Sprayed on three lots of pupae, about 

 50 per cent, were killed. They died very much as did those from acids in 

 the foregoing cases. For exami)le, one lot of two dozen pupae was 

 treated with the alcohol solution in the evening. The next morning 

 five were weak (dying), six were half-molted and dying, four were 

 emerged and dying, the others all right. 



To prevent ovipositing. 



Experiments to repel the insects from trees and prevent the females 

 from ovipositing were made as follows : On the 20th of June the Cica- 

 das were numerous and active, depositing their eggs in a thicket of 

 lilac bushes, which were low and hence easily inspected. On these the 

 milk-kerosene emulsion (60 per cent, kerosene) was tried to test its 

 effects as a preventive. It was api:)lied in different places in three 

 strengths, viz: 



Parts by volume. 



1. Emulsion 1 



Water 2 



2. Emulsion 1 



Water 5 



3. Emulsion - 1 



Water 10 



The first dilution was so strong that it injured many of the leaves, and 

 its odor was very distinct in the air among the bushes during the day of 

 its application, and still iDerceptible on the following day. The other 

 dilutions had no effect on the foliage and from them no odor appeared, 

 except by scenting close to the surfaces treated. 



Within two hours after the applications were made the Cicadas began 

 ovipositing again in the bushes which had been sprayed. During the 

 lirst afternoon and in the forenoon of the next day ovipositing in these 

 bushes went on as rapidly as in those that had not been sprayed. The 

 i!2 sects were even driven ofi' in the movements incident to the inspec- 

 tion of the work, but at any time when not disturbed a few could be 

 seen inserting the ovipositor in the trees treated. 



Further experiments were made with raw linseed-oil and with white- 

 wash as preventives of this injury. Each of these substances was 

 painted upon the twigs of six young peach trees and on some lilac 

 bushes, all of which had been much visited and more or less injured 

 previously by Cicadas. But at the time of the application (June 22) the 

 weather became cloudy, breezy, and cool) and bo coutinaed £or some 



