Plant Galls 



1 Long spruce cone gall, Chermes cooleyi Gill. 



2 Hackberry nipple gall, Pachypsylla mamma Riley. (After 



Thompson) 



3 Red pouch gall. Pemphigus rhois Fitch. (Author's illustration) 



4 Hickory leaf gall produced by Phylloxera caryae-avellana 



Riley. (After Thompson) 



5 Hickory leaf gall produced by Phylloxera caryaefallax Riley. 



(After Thompson) 



6 Hickory leaf gall produced by Phylloxera caryaeglobul-i Walsh. 



(After Thompson) 



7 Hickory leaf gall produced by Phylloxera rimosalis Perg. (After 



Thompson) 



8 Hickory leaf gall produced by Phylloxera caryaesemen Walsh. 



(After Thompson) 



9 Axillary Spiraea bud galls infested by C e c i d o m y i a sp. (After Clarke) 



270 



