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Indiana University Studies 



torn, more convergent posteriorly than in illustrans; foveae quite broad, 

 rounded, almost wholly smooth at bottom ; mesopleurae quite finely acicu- 

 late centrally; abdomen reddish rufous basally; length 1.7-2.2 mm., less 

 than in operator. 



MALE. — Shows the secondary sexual characteristics of the species, 

 and further agrees with the female of this variety; length 1.5-2.0 mm. 



GALL. — Similar to the galls of the bisexual forms of the other 

 varieties; large, up to 55. mm. in diameter, becoming golden brown on 

 aging; on Quercus ilicifolia. 



EANGE. — Rhode Island: Providence (Thompson). New York: 

 Staten Island (Beutenmuller and W. T. Davis). New Jersey: Plain- 

 field, New Brunswick, Milltown, Hornerstown (in Amer. Mus. Nat. 

 Hist.). Possibly confined to a northern part of the Atlantic Coastal 

 Plain. 



TYPES. — 14 females, 1 male, 4 galls. Holotype female, paratype 

 females, males, and galls at The American Museum of Natural History; 

 paratype females and gall with the author. Labelled Staten Island, New 

 York; June, 1893; Q. ilicifolia; Beutenmuller collector. 



Falsus is to be recognized by the only moderately widened 

 parapsidal grooves, the smooth, romided fovese, and the small 

 size. On the whole this variety more nearly agrees with the 

 other southern varieties than it does with illustrans, the more 

 northern form on Q. ilicifolia. I have examined insects of 

 falsus from the localities listed, and find them quite uniform. 

 The Bassett material purporting to be from ilicifolia at Water- 

 bury, Connecticut, belongs to variety operator. Certainly two 

 varieties, falsus and illustrans, occur on this one oak, and pos- 

 sibly the third, operator. The geologic histories of the dis- 

 tinct areas occupied by each variety may be responsible for the 

 development of the distinct insects. I do not know whether 

 other black oaks in the same part of the Coastal Plain have 

 this same variety. 



The galls which I figured (1920, Bull. Amer. Mus. Nat. 

 Hist., XLII, pi. XXXI, figs. 30, 31), are from ilicifolia near 

 Providence, Rhode Island, and probably represent the under- 

 scribed, agamic form of falsus. 



Andricus operator variety illustrans, new variety 

 form illustrans, new form 



Calliryhtis operator Stebbins, 1910, Springfield (Mass.) Mus. Bull., II, 

 p. 25, fig. 47. Thompson, 1915 (Mass. record), Amer. Ins. Galls, 

 pp. 11, 30. 



Andricus operator form operator Kinsey, 1920 (in large part), Bull. 

 Amer. Mus. Nat. Hist., XLII, pp. 345, 380. 



