14 



BULLETIN 847, U. S. DEPARTMENT OE AGRICULTURE. 



Table IV shows that out of 121 individuals, 2 issued from the 

 wood as beetles the next year after the eggs were deposited, 103 is- 

 sued in two years, 15 in three years, and 1 in four years. 



Eecords of the exact number of days elapsing from the deposition 

 of the eggs to the issuing of the beetles were ascertained in a number 

 of instances. These records are shown in Table V. 



Table V. — Number of days between deposition of egg and emergence of beetle 

 of roundheaded apple-tree borer at French Creek, W. Va. 



Date egg was deposited. 



June IS, 1913 . 

 Do....... 



Do 



June 15, 1914 . 

 June 18, 1914. 

 June8, 1914.. 

 June 12, 1914 . 

 June IS, 1914. 

 June IS, 1913. 

 June IS, 1914. 

 June 16, 1914. 

 June IS, 1914. 

 June 11, 1914. 

 June IS, 1913. 

 June 11, 1914. 

 June 16, 1914 . 



Total... 



Date beetles issued from 

 wood. 



June 1,1915.. 

 June 14, 1915 . 

 June 8, 1915.. 

 May 24, 1916. 



do....... 



May 25, 1916.. 



do ... 



May 26, 1916. 

 May 27, 1916.. 



do 



May 28, 1916.. 



do.. 



do 



do.. 



do 



May 29, 1916.. 



Number of beetles. 



Male. Female. 



10 



Number 

 of days 

 from egg 

 to beetle. 



713 

 726 

 720 

 708 

 705 

 716 

 712 

 707 



1,073 

 708 

 711 

 709 

 716 



1,074 

 716 

 712 



As is shown in Table V, 1 male spent 1,073 days in undergoing 

 development within the tree and 1 female 1,074 days, a 3-year period 

 for each. All the others reached maturity in 2 years,, the 9 males 

 requiring on an average 710 days from egg to adult and the 9 

 females undergoing the same transformation in an average of 714 

 days. 



Eecords obtained at Winthrop, Me., show that of 24 individuals, 

 none matured in 2 years, 6 issued as beetles in 3 years from the egg, 

 and 18 required 4 years to develop from eggs to adults. No definite 

 records were obtained for individuals requiring longer than 4 years 

 for development and yet observations were made which indicate a 

 5-year period in some cases. Observations made at Biltmore, 1ST. C, 

 indicate a 2-year period with most individuals in that locality. 



THE PUPA. 



The pupa (PI. VII, A), when first formed, is soft and delicate, 

 the color being similar to that of the larva. Within a few days it 

 turns slightly yellowish, the eyes soon take on a dark color, and later 

 the whole body becomes mottled with brown and blackish markings. 

 The pupa occupies a vertical position in the cell and measures from 

 18 to 25 mm. in length, the females being much longer and more 

 robust than the males. 



