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NEW YORK STATE MUSEUM 



tion showed a very larj^e proportion of the twigs to be badly affected* 

 The extent of the infestation is indicated in figure 9, a drawing 

 made from one of the samples. Mr A. D. Tilton of the entomology 

 department, Massachusetts Agricultaral College, submitted an oak 

 twig showing a very serious infestation and stated that the insect 

 had killed the tree. 



Fig. 9 Ribbed bud gall, A n d r i c u s 

 gemmarius Ashm. Badly infested 

 twig and one gall enlarged. (Original) 



The deformations following attack by this insect are so large and 

 irregular, practicaUy girdling the twigs in many cases, that they 

 probably seriously interrupt the flow of the sap and weaken the 

 portion of the limbs beyond the point of injury to such an extent 

 that in a few years they are likely to break off. The developing 



