AMERICAN PLUM BORER, 5 



vertex; third joint lanceolate, nearly as long as the second. Abdomen extending 

 beyond the hind wings; hind borders of the segments pale cinereous; wings moder- 

 ately broad; fringe long, cinereous. Fore wings hardly acute; middle and exterior 

 lines cinereous, undulating, blackish-bordered; discal mark cinereous, curved; mar- 

 ginal points black; exterior border convex, hardly oblique. Hind wings dark ciner- 

 eous, very slightly hyaline; marginal line brown. Length of the body 5 lines; of the 

 wings 12 lines. 

 a. Korth America. From Mr. Carter's collection. 



SPRING PUPATION OF WINTERING LARVAE. 



At Winchester, Va., in the spring of 1913, pupation of the wintering 

 larvae began about the last of March to the first of April. Frequent 

 collections of larvae were made previous to and including March 24, 

 and pupation had evidently not begun up to that time. Absence 

 from Winchester prevented further observation for a period of 14 

 days following March 24, and during this interval, of the 31 larvae 

 that had been taken in the field previous to that date, 18 had pupated 

 by April 7. However, the temperatures from April 4 to April 7 

 were so extremely low that insect life generally was almost dormant 

 and most of this pupation must have occurred before the former date. 



Girault in 1906 records the pupation of three larvae under his 

 observation in the insectary at Washington, D. C, as occurring on 

 March 27, 28, and 31, respectively. At Myrtle, Ga., in the same 

 year, both Rosenfeld and Girault observed pupation as early as 

 March 2, or about 25 days earlier than in the latitude of Washington. 

 Girault, in 1905, took four pupae in the field at Myrtle, Ga., March 1. 

 In the latitude of northern Virginia and the District of Columbia, in 

 a normal season, pupation evidently begins about April 1 or possibly 

 a little before, depending upon the relative lateness of the season, 

 and as far south as Georgia probably a month earlier. 



The 23 individual records of the pupal stage included in Table I 

 were taken from field-collected material kept in an out-of-doors rearing 

 shelter. In most cases the larvae under observation were kept in 

 their winter cocoons (PL II, c), which are so loosely woven that 

 the transformation of the insect within can be easily seen. Occa- 

 sionally it was necessary to force the larvae to spin up in glass vials, 

 but this was avoided as far as possible, as the insect under such con- 

 <1 it ions probably does not feel the full effect of the changes in outside 

 temperature. 



