July, 1914.] 



THE APPLE MAGGOT. 



19 



DISTRIBUTION AND DESTRUCTIVENESS. 



The present known distribution of the apple maggot approxi- 

 mates in general the limits of the eastern, or humid, part of the 

 Transition Life Zone, in other words the so-called Alleghanian 

 Zone. The area comprised within this zone, as defined by Dr. 

 Merriam in 1900, is indicated in Chart 1. 



Chart 1 . The Alleghanian Life Zone (shaded area) . The known distribu- 

 tion of the apple maggot agrees approximately with this zone. For exceptions, 

 and for details of distribution, see text. 



The maggot reaches its greatest abundance and destructive- 

 ness in Maine, New Hampshire, parts of Vermont, in Massachu- 

 setts, parts of Connecticut and New York, with an additional 

 wide, though scattering distribution in Ontario, Michigan and 

 Pennsylvania. 



Notes on the occurrence of the species in the several states 

 and provinces have kindly been furnished the writer by ento- 

 mologists. These are here summarized: 



