183 



ences between these species are so slight, however, that no one but a 

 specialist would detect theui, and the habits are practically the same 

 for all. 



EXPERIMENTS WITH KEMEDIES. 



Judging from the results obtained by Mr. Slingerland, the period of 

 my two examinations of Mr. Emory's orchard was not favorable for 

 the application of remedies, the trees being covered with adults and 

 the leaves being rapidly stocked with eggs. Kevertheless, to satisfy 

 myself as to the effects of various washes on the eggs, a variety of 

 careful tests were made. Young trees were selected, the leaves of 

 which were well covered with eggs, and were very carefully and thor- 

 oughly sprayed with the mixtures. The a[)plications were all made on 

 the 31st of July, on a very hot, scorching afternoon, and the following 

 days were of a similar character, no raiu of any importance falling 

 for nearly a week. The insecticides experimented with were milk and 

 whale-oil soap kerosene emulsions diluted M'ith 9 and 7 parts of water, 

 and the soap enuilsion also with 4.^ parts of water; the resin wash ; and 

 an emulsion made by using the resin wash in lieu of soap, with kero- 

 sene, this being also diluted with 9 and 7 parts of water. ISTotes takeu 

 on the day following, and the two or three subseciuent days, indicate 

 that with the stronger mixtures of each of the three emulsions men- 

 tioned there was a slight change in the appearance of various per- 

 centages of the eggs on the leaves. This change consisted in their 

 assuming a reddish orange color, quite unlike the normal tint of the 

 newly deposited egg, and also much darker and more uniform than 

 tlie color assumed by the egg Just before hatching. The young larvje 

 disclosed at the time of the application were destroyed in every case. 

 Examination of the leaves ten days after treatment indicated that 

 this yellowing of the eggs really had resulted from the action of the 

 insecticides, the eggs so colored having failed to hatch, and were, for 

 the. most part, shrivelled and dead. From 75 to 95 per cent of the 

 eggs wei'e killed with the 7-times diluted emulsions, and more than 

 half as many with the emulsions 9-times diluted. The results for each 

 mixture may be more accurately summarized as follows: 



Milk euiulsion diluted !> times: From 3 to 5 per cent of the eggs dead; one-balf 

 hatched; balance apparently uuiujured. 



Milk emulsion diluted 7 times: 25 per cent of the eggs hatched; balance shriv- 

 elled, showing etfect of wash. 



Whale-oil soap emulsion diluted 9 times: 25 per cent of eggs hatched; condition 

 of remainder doubtful. 



Whale-oil soap emulsion diluted 7 times: 75 per cent killed; 5 per cent hatched; 

 condition of the rest doubtful. 



Whale-oil soajj emulsion diluted -11 times: 8 to 5 per cent hatched; balance dead; 

 discolored or afl'ected by the wash. 



Resin-wash kerosene emulsion diluted 9 times: 25 per cent of eggs h^itched; 25 

 per cent killed; 50 j)er cent not certainly injured. 



