114 



JOURNAL OF ECONOMIC ENTOMOLOGY 



[Vol. 2 



LIFE CYCLE OF FOUR HARLEQUIN BUGS 



* Indicates that molt occurred some time between 5 p. m. and the following 8.30 a. m. 



As evidence that the duration of the Ith and 5th instars may vary it 

 is only necessary to study the above table, and as further proof com- 

 pare these dates with the time recorded by Chittenden, as above men- 

 tioned. He states: "The first or egg stage covered 11 days. The 

 time from the hatching- of the eggs until the first molt gave the first 

 larval instar or nymph period. 7 days; the second instar required 13 

 days ; the third. 8 days ; the fourth. 14 days, while the fifth or pupal in- 

 star covered 17 days, a total of 70 days or 10 weeks . . . " 



Means of Suppression 



From an economic standpoint this work indicates that Harlequin 

 bugs should be fought vigorously in the fall, particularly after Sep- 

 tember 1st, in order to prevent the young forms from maturing and 

 going into hibernating quarters. It also serves to emphasize the fact 

 that the adults first appearing in spring should be collected or other- 

 wise destroyed before they commence egg deposition. I am convinced 

 that the hibernating adults are more prolific than the succeeding gen- 

 erations, which makes it most advisable to destroy them late in fall or 

 early in spring. 



Parasites succeed in destroying a large per cent, of the eggs, but in 

 all my work this season with nymphs and adults no parasites were se- 

 cured from them. 



President Forbes: The next on the program are papers on api- 

 culture by :\rr. E. F. Phillips and Mr. B. N. Gates. 



