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NEW YORK STATE MUSEUM 



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observed in the vicinity of the trees, and it was probably this 

 species which preyed on the bark beetles. This is a striking 



illustration of the value of woodpeck- 

 ers and their perseverance in digging 

 out such small insects. These pupae 

 were undoubtedly the progeny of the 

 fall brood of beetles, which were ob- 

 served Sep. 7, 1900, entering trees in 

 large numbers. Aug. 1, 1901, adults of 

 Scolytus in some numbers were 

 entering the bark of a young dying 

 appletree, a victim of S a p e r d a 

 Candida, at Pittstown N. Y. The 

 bark beetles gnawed many minute 

 holes about ~ 6 - of an inch deep and of 

 the same diameter. Some of these 

 holes were deserted, and in other 

 places the beetles were at work mak- 

 ing the primary entrance or beginning 

 a gallery. This observation in connection with the preced- 

 ing ones shows very clearly that the fall brood of beetles, 

 if there be a distinct one, as is very probable, extends 

 in the eastern part of New York state from Aug. 1 till Sep. 

 7 or later. This is still further confirmed by our finding at 

 Ripley N. Y. Sep. 5, 1901, beetles entering plumtrees in large 

 numbers. 



The presence of pupae and recently transformed beetles in the 

 plumtrees examined May 22 would indicate that the adults 

 would probably have emerged within a short time. There are 

 therefore at least two generations annually in New York state, 

 and the short period necessary for the completion of the life 

 cycle permits more. It may be that more do occur, but there 

 does not appear to be any good evidence to that effect, at pres- 

 ent. Another cheering feature in the last mentioned attack 

 was the breeding of numbers of the beneficial parasite known as 

 Chiropachys colon Linn. 



Fig. 7 Work of fruit tree bark 

 beetle in plum (original) 



