REPORT OF THE STATE ENTOMOLOGIST I9OO 997 



7 pound to 10 gallons 



June 8. 110 caterpillars dead, 105 liviug 

 9. 29 caterpillars dead 

 15. 6 caterpillars dead 

 19. 10 caterpillars dead : 72% of the total killed. 



The experiment was continued to the end, and the caterpillars not killed 

 developed 34 parasites, 20 male and but eight female moths, and a num- 

 ber died in their cocoons from some other cause. No moths developed 

 from those sprayed with the stronger solution of tobacco whale oil soap. 

 This latter soap appears to be much more effective for this kind of work 

 than the ordinary preparation. Experience emphasized the necessity of 

 thoroughly drenching the caterpillars with the insecticide, if the best 

 results were to be obtained. A moderately fine spray was much more 

 economical of the solution and gave better results than a very coarse 

 spray. 



This species was attacked by a large number of parasites, and in some 

 localities the pests were nearly exterminated in limited areas. A. lot of 

 100 cocoons were collected at Slingerlands (N. Y.) June 28, and the 

 natural enemies of this species bred from them. 46 parasites were obtained, 

 2 1 of which were either Pimplas or Theronia fulvescens Cress., a 

 secondary parasite and an enemy of the Pimplas, and a considerable pro- 

 portion of the remainder belonged to the Tachinidae. The thorough- 

 ness of this parasitism was strikingly shown by a lot of cocoons from 

 Altamont submitted for examination by Judge J. W. McNamara. Over 

 90 % had been killed by parasites. Pimpla conquisitor Say and 

 P. inquisitor Say were the two most abundant and effective parasites 

 in many localities. The females were present in considerable numbers 

 at Slingerlands, and could be seen investigating the cocoons and occa- 

 sionally thrusting the ovipositor through the meshes. Theronia ful- 

 vescens Cress, was almost as numerous as either of the two preceding 

 species. It was taken at Slingerlands, and also reared from cocoons re- 

 ceived from Glens Falls.. Anomalon exile Proy. was reared in 

 smaller numbers from cocoons received from Lyon Falls and Glens Falls. 

 Pteromalus vanessae How. was reared in considerable numbers 

 from cocoons collected at Glens Falls. Tachina mella Walk, was a 

 valuable parasite in many localities, and a large number of flies could 

 have been reared. The latter part of June, when the forest tent-cater- 

 pillars were crawling everywhere, one was attacked by a common wasp, 

 Polistes pallipes St Farg. Two wasps were engaged in the bat- 

 tle. They cut the caterpillar in two, and one began feeding on a portion, 

 while the other hung around, evidently anxious to get at the delicacy. A 



