PERGANDE — NORTH AMERICAN PHYLLOXERINjE. 



233 



side ; no galls of any other species could be detected on any of 

 the leaves. Notwithstanding this fact, it is still possible that 

 these new galls were the product of some other species, the 

 winged form of which may have migrated there from some dis- 

 tance. These newly formed galls were smaller and also quite 

 different in appearance. Their upper surface is also scarcely 

 elevated above the plane of the leaf, with the centre quite dis- 

 tinctly depressed. This depression is reddish or pink and is gen- 

 erally encircled by a pale yellowish-green ring, the under side is 

 more prominent, though by no means conical, and somewhat 

 paler than above. All contained, besides the females, numerous 

 eggs and also a few larvae. The female is yellow with the eyes 

 black, the larva pale yellow with reddish eyes; the eggs are 

 colorless, the more mature ones faintly yellowish. 



Var. A. Phylloxera vasculosa Pergande. 



This variety is more striking in appearance and much larger 

 than the more common or typical form. It grows also on the 

 under side of the leaves, but is rather scarce, there being not 

 more than from one to perhaps twelve or a few more upon a tree. 

 Its upper surface is very much like that of the typical form, 

 thougk it is often considerably sunken below the plane of the 

 leaf and is of very much the same color. The galls proper, on 

 the under side, are very much of the shape of a vase or urn. 

 They are more or less constricted at base, the sides rounded and 

 of a pear- or more or less globular form. The opening at tip, 

 which is closed while the galls are immature, opens at maturity 

 into bracts, similar to those of the typical form, whereby a more 

 or less distinct neck is produced. The color of the galls is pale 

 green, or sometimes almost white or pale yellowish, the surface 

 being quite pubescent. Their diameter across the widest part 

 ranges generally between 5-8"™-, and their vertical diameter 

 between 4-10™™-. 



Var. B. Phylloxera purpurea Pergande. 



This form or variety is in shape between the typical form and 

 var. A. It is of about the same size or somewhat larger than the 

 first. Its base is constricted and the remaining pait beyond it 



