39S 



JOURNAL OF ECONOMIC ENTOMOLOGY 

 RECORDS OF THE PUPAL INST AR— Concluded 



[Vol. 6 



Gillette and Weldon ^ state that the pupal stage occupies about ten 

 days in the vicinity of Canon City, Colo. 



It appears thus that the larvae pupate on the average nearly a month 

 earlier in Cahfornia than in Colorado and that the pupal instar occu- 

 pies almost double the number of days in the former state as in the 

 latter. The first of these phenomena is to be expected when it is 

 considered that larvae hatch from the winter eggs much earlier in 

 California than in Colorado, Gill ^ in his paper stating that "During 

 the season of 1912, in the orchards, the eggs were hatching from April 

 20 to May 9, . . ." A comparison of the meteorological condi- 

 tions influencing respectively Colorado and California pupae might 

 explain the difference in the length of the instar in the two locahties. 



< Gillette and Weldon, "The Fruit-tree Leaf-roller in Colorado," Colo. Agr. Exp. 

 Sta. Circ. 5, p. 6. 



' U. S. Dept. Agr. Bull. 116, pt. 5, p. 102. 



