April 1S89.] 



PSrCHE. 



185 



Andricus cornigera O. S. When 

 Baron Osten Sackeu described the gall 

 of this fly he had never seen the cynip 

 that produced it. His specimens were 

 taken on the pin oak, ^. palustrts. 

 The galls in my collection supposed to 

 belong to this species were all taken on 

 the red oak and may pro\'e to be a new 

 species. I have taken a considerable 

 number of these galls and they all difler 

 from a beautiful type which I have from 

 the pin oak b}- being very much darker 

 in color and more irregular and rough 

 in outline. The galls appear like knott}' 

 swellings completelv surrounding the 

 small limbs. From all sides of the gall 

 little seed-like bodies, much the shape 

 and size of a small barley corn, are 

 pushed out. These contain the larvae 

 of the gall-fly and fall to the ground 

 some time in Jidy, leaving the gall full 

 of holes. I have a single imperfect 

 fly taken from an immature gall. 



Andricus futilis O. S. I have 

 searched in vain for this gall in the vi- 

 cinity of Lansing, but late in the fall of 

 1887 I found a small ^. alba in Ionia 

 county, Michigan, standing in an open 

 field, that had galls of this species on 

 nearl}- every one of its dried leaves. The 

 flies had made their escape so that no 

 insects were reared. 



Andricus punctatus Bass. Galls 

 rare, but ai^e occasionally found on 

 small limbs of ^. rubra. They vary 

 from one half of an inch to two inches 

 in diameter and are smooth knotty 

 swellings surrounding the limbs much 

 the same as the galls of A. cornigera. 

 From these galls I have reared the guests, 



Ceroptres petiolicola., Synergjis ligni- 

 cola and an undetermined species ; also 

 the parasite Decatoma varians., but no 

 true gall-flies. 



Andricus semitiator Harr. The 

 iDrown, woolly galls, so common on the 

 twigs of ^. alba in midsummer, are the 

 product of this cynip. Galls gathered 

 early in Julv gave flies the seventh of 

 the same month. A green parasitic fl}', 

 a species of Syntojnaspis., I have reared 

 from these galls in fully as large num. 

 bers as the true gall-maker. No guests 

 have been reared. 



Audrictis scitulus Bass. This species 

 seems rare. I have taken a few of the 

 galls on ^. rubra in the vicinity of 

 Lansing, Mich., and near Ames, Iowa. 

 In the latter case the galls were taken 

 July 5, when the flies were found to be 

 already escaping. A few specimens of 

 two undetermined parasites were also 

 reared. The galls are composed of a 

 woodv enlargement of the tips of the 

 twigs. 



Andricus Jlocci \\'alsh. ( Cynips lana 

 Fitch.) Walsh marks this species-"rare." 

 I took a number of the galls from the 

 leaves of ^. alba and ^. macrocarpa 

 in Michigan and find it to be one of 

 the most common galls on both these 

 oaks at Ames, Iowa. The galls appear 

 as little bunches of brown wool grow- 

 ing out from the mid- rib, or one of the 

 main-veins, on the under side of the 

 leaves. Beneath the wool is a cluster of 

 small' seed-like bodies about as large as 

 a very small kernel of wheat. Galls taken 

 in Michigan late in the fall gave flies 

 March 20. A few parasites, but no 



