INSECTS AFFECTING PARK AND WOODLAND TREES 



647 



Birch seed gall midge. Oligotrophies betulae Winnertz. Deformed cat- 

 kins of white birch produce enlarged seeds, each containing a reddish, legless 

 maggot. 



This Europeari species is rather common about Albany and is of 

 interest because of the peculiar deformity it produces in birch seeds. The 

 larvae become full grown early in October, at which time a windowlike 

 spot is easily discerned on the surface of the seed. The normal alate or 

 winged seed is transformed by this insect into a nearly globular form with 

 the alae rudimentary. 



Surmc tomato gall. Pemphigus rhois Fitch. Somewhat pear-shaped or 

 round, reddish galls of different sizes occur on sumac leaves in September. 



These galls are rare in the vicinity of Albany. They are quite variable, 

 round, spheroid in form, with the surface uneven and usually slightly 

 knobby. The face exposed to the sun is normally bright crimson and the 

 interior is sometimes thickly crowded with plant lice. These galls occur on 

 Rhus glabra and R. t y p h i n a. [See pi. 49, tig. 3.] 



Hackberry nipple gall. Pachypsylla celtidis-mamma Riley. This gall 

 is represented by a cup-shaped depression on the upper side of the leaf ; 

 beneath it is broadly rounded and about y± inch in diameter. It is common 

 on hackberry. 



Rose root gall. RJwdites radicum Osten Sacken. This large, smooth, 

 reddish brown gall occurs on the roots of various wild roses. It is deeply 

 incised at the point of attachment to the roots. The interior is pithy 

 and contains numerous cells. 



Rose bedegar. Rhodites rosae Linn. Curious, curved, fibrous, moss- 

 like masses occur on rose and blackberry bushes. This peculiar gall is 

 composed of a mass of hard cells formed around a branch and is entirely 

 covered with long, dense, green filaments forming a mosslike mass \ x / 2 

 inches or more in diameter. 



Mealy rose gall. Rhodites ignota Osten Sacken. Irregular, spheric 

 galls about the size of a pea, covered with a white mealy substance, are 

 rather common on wild rose in the vicinity of Albany. Occasionally several 

 of these galls coalesce, forming an elongated, irregular mass. The gall is 

 a woody one and contains several cells. 



Spiny bullet gall. Rhodites bicolor Harr. Round galls a third to 

 nearly half an inch in diameter, covered with prickly spines about as long as 

 the diameter of the galls, are common on twigs of different kinds of wild 

 roses. This gall is yellowish green sometimes tinged with red and occurs 

 in clusters of two or more. 



Globular rose gall. Rhodites globulus Beut. A smooth, rounded gall 

 arising abruptly at each end from the branch, occurs on wild rose on Staten 

 Island. It has a rather soft corky texture and contains numerous cells. It 



