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which sometimes kills that portion beyond it. These galls vary in length 

 from one to three inches, and also considerably in diameter, depending- 

 somewhat on the size of the twig. The writer observed these swellings, 

 during the autumn of 1904, iipdn thrifty shoots measuring half an inch 

 in diameter, the galls increasing this to one inch. On June 10th, 1904,. 

 quite a large amount of the work of these larvae was observed near 

 Logan, Ohio, and in every case the sawdust was ejected from a point in 

 the axil of a small side, branch. The twigs were very tendei and watery 

 and the larvae about three-eights of an inch in length. 



Fig. 8. Black locust twigs showing galls caused _ by larvae of the Locust Twig 

 Borer {Ecdytolopa insiticiana). Naturafsize. (Original.) 



The larvae continue to feed in the tender twigs until they have reached 

 maturity, about October 1st, at which time they leave the gall through 

 an openmg which has heretofore served as an outlet for the' sawdust' 

 Descendmg to the ground they proceed to construct silken cocoons among 

 the dried leaves. Sometirnes they crawl under a leaf and fasten one- 

 side of the cocoon to it, the other being covered '.with grains of sand. 

 1 he adults appear about October 20th. , ' 



The larva when full grown is about half an inch in length, ancf 

 reddish-brown in color; head light brown. The pupa measures about 

 two-fifths of an inch in length and is vellowish-brown in color The 



