IOWA ACADEMY OF SCIENCES. 113 



Acraspis villosus Gill. Rep. Mich. B'rd Agr., 1887, p. 474. Psyche, v. V, 

 p. 218. 



Galls much resembling those of the preceding species, of a light yellow 

 color, with longer and more dense growth of hairs, always globular and 

 single-celled, attached to the under side of the leaves of Q. macrocarpa. 

 Flies emerge in October. Michigan, Iowa. 



Acraspis 7iiger GWl. Bull. 7, la. Exp. Sta., p. 282; Ent. Amer., v. VI, p. 23. 



The galls are perfectly globular in form, from one-fourth to three-eighths 

 of an inch iu diameter, and are covered with a short, dense pubescence, 

 which gives them the appearance of felt on their outer surface. Attached 

 to the under side of the leaves of Q. alba and Q. ma«rocarpa. The galls 

 mostly fall before the leaves, and the flies emerge the following summer. 

 Michigan, Iowa. 



Acraspis macrocarpce, Bass. Trans. Am. Ent. Soc, v. XVII, p. 84. 



The galls are hard, egg-shaped excrescences from two to three-eights of 

 au inch ia length, occurring usually on the under side of the leaves of Q, 

 macrocarpa and always attached to a vein. The black, wingless gall-flies 

 emerge in October. New York, Ohio, Michigan, Iowa. 



Biorhizajorticornis Walsh. Proc. Ent. Soc. Pha., v. II, p. 490. 



A large number of the galls are usually crowded together about a young, 

 thrifty shoot of Q. alba. They remind one of a large number of puff-balls 

 closely crowded together, or of closely packed figs. The galls are yellowish 

 in color, and each has a larval cell, held in place by radiating fibers. This 

 species is also wingless, the insects emerging in the spring. New York, 

 Illinois, Michigan, Iowa. 



Biorhiza rubinus. Gill. Rep. Mich. B'rd Agr., 1887, p. 472. Psyche, v. 

 V, p. 215. 



The galls are small, globular, juicy bodies from two to three inches in 

 diameter, occurring upon the leaves of Q. alba in October. Flies emerge the 

 following summer. Michigan, Iowa. 



Eolcaspis duricoria Bass. Trans Am. Ent. Soc, v- XVII, p. 64. 



Producing sub-globular sessile galls surrounding twigs of Q. macrocarpa 

 and Q. bicolor. The galls are from three to four-eighths of an inch in diam- 

 eter, and usually terminate in a small teat-like point. They are of a dense, 

 corky material, and each has a free egg-shaped larval cell at its centei-. The 

 galls are often so crowded together as to be much pressed out of shape. 

 Flies emerge in October. Connecticut, Michigan, Illinois, Iowa. 



Eolcaspis globulus Fitch. Proc. Ent. Soc. Pha., v. II, p. 328. 



The galls are globular, of a corky structure, like the preceding, occurring 

 singly on the twigs of Q. alba and Q. montana. Flies emerge in October. 

 Connecticut, Michigan, Iowa. 



Dryophanta papula Bass. Can. Ent., v. XIII, p. 107. 



The galls are very hard, irregular swellings upon the upper surface of the 

 leaves of Q. rubra and Q. coccinea. The galls often have many sharp cone- 

 like points. Flies emerge about July 10. Massachusetts, Connecticut, Mich- 

 igan, Iowa. 



Dryophanta liberce-cellula^ Gill. Bull. 7, la. Exp. St., p. 283; Ent. Amer., 

 V. VI, p. 24. 



The galls are globular, from two to throe-eighths of an inch in diameter, 

 and grow through the blades of the leaves of Q. rubra and Q. coccinea. The 



