212 TRANSACTIONS OF THE ILLINOIS 



Tribe III. Pemphigin.«. 



A. Cubital vein forked at the tip. — Sckizoneura. 

 AA. Cubital vein simple. 



a. Hind wings vv'ith two oblique veins. — Pemphigus, 

 aa. Hind wings with one oblique vein. 



b. Wings deflexed in repose. — Tetranetira. 

 hb. Wings horizontal in repose. — Aploneura. 



Tribe IV. Rhizobiin^.. 



A. Third joint of the antennas much longer than the fourth. — Forda. 

 AA. Third and fourth joints of the antennae nearly equal in length. — Rhizobius. 



Tribe V. Tychein^e. 

 Only one genus in the tribe. — Tychea. 



Tribe VI. Chermessin^. 

 A. Antennae five-jointed. 



a. Fore wings with four oblique veins ; the cubital vein forked. — Vacuna. 

 aa. Fore wings with three oblique simple veins. — Chermes. 

 A A. Antenna; three-jointed. — Phylloxera. 



As I expect in my next report to give a more complete account of these insects, 

 and to arrange according to the latest authority, I will not attempt at present to arrange 

 the species mentioned in this paper under Passerini's divisions and genera. I will only 

 add that in this synopsis Sckizoneura corresponds with Eriosotna, as I have given it ; 

 V'acuna to Thelaxes; and Adelges, as I have used it, is probably included in Chertnes 

 by Passerini. 



A 



