PERGANDE — NORTH AMERICAN PHYLLOXERINjE. 249 



ish-green, and often beautifully red on one side while young, 

 turning brown or black and soon drying up after the architects 

 have left. 



Migratory female. — Length of body about i.2"""'. Expanse 

 of wings 3.4-3.6'"™- or more. Color paler or darker yellow, the 

 head, mesothorax and sternum black or brown, the antennae and 

 legs dusky, the eyes brown or black. Antennae long and slender; 

 joint I longer than wide and of uniform diameter ; joint 2 more 

 slender than usual, of almost uniform diameter, rounded at tip, 

 with more or less distinct scaly annulations ; joint 3 long and 

 slender, its anterior sensorium only about one-fourth the length 

 of the joint ; the lower one very small, often almost obsolete ; 

 greater part of the joint, at least as far as to the anterior sensor- 

 ium, distinctly and quite coarsely annulate, the rest being scaly. 

 This joint is often quite irregular in shape, the more common 

 form as represented in the figure. Head and thorax finely rugose ; 

 the abdomen quite densely and finely striate, the striae closely 

 lined with minute sharp points. Legs rather long and robust. 

 Wings large, rather broad, pale dusky or brownish ; stigma 

 and discoidal vein darker ; the discoidal branch and the stig- 

 mal vein sometimes almost obsolete ; all more or less shaded. 

 Sometimes the stigmal vein passes the stigma and connects with 

 the discoidal vein near its base. The hind wings are also large 

 and rather broad and their subcostal vein sometimes almost com- 

 pletely obliterated. 



Phylloxera Georgian a" Pergande, n. sp. 



Plate XV., figs., 1 1 5-1 17. 



The galls of this species closely resemble those oi Ph. devastatrix, 

 being of the same^shape, size and color ; but the winged form is 

 quite different and may readily be distinguished by its much paler 

 wings and venation and particularly by the shorter antennae and 

 much larger sensorial membranes of the third joint. 



The galls grow either singly or in close clusters upon the tender 

 twigs and petioles and often recall in appearance the galls of 

 Cynips q.-ficus. Those growing in clusters are more or less irreg- 

 ular in shape, whereas those growing singly are quite globular 



