162 TRANSACTIONS OF THE ILLINOIS 



and another on the apex of the veins of the fore wings ; the stigma white, 

 with a brown streak at each end : the second vein is wavy, and at its tip 

 is curved toward the tip of the first vein, 



25. Aphis (?) maculella, Fitch. The Little Spotted-winged Hickory 



Plant-louse. 



Differs from A. caryella in having only a slender black ring at each 

 articulation of the antennse ; the feet, and a band near the tips of the 

 hind thighs, blackish ; the fourth vein of the fore wing with a black dot 

 on its base and a dusky one on its apex ; the first vein, apical third of the 

 second vein, and the first and second forks, broadly margined with smoky 

 brown ; second vein wavy and parallel with the tliird till near its tip, 

 where it curves toward the first vein. 



26. Aphis (?) funipeiinella, Fitch. The Little Smoky-winged Hickory 



Plant-louse. 



Is of a dull yellow color, with blackish feet, and the wings smoky, 

 with robust brown veins ; the rib-vein much more distant from the mar- 

 gin the first half of its length than in the other species. 



27. Aphis (?) marginella, Fitch. Little Black-margined Hickory Plant- 



louse. 



Pale yellow ; antennae white, except at the base, and four bands 

 which are black ; a deep black band in front, between the eyes, and con- 

 tinued along each side of the thorax to its base ; fore wings pellucid ; stig- 

 ma, outer margin and rib-vein coal black ; first vein with a black dot on 

 its base; fourth vein, black; rest, colorless; outer margin of the hind 

 wings, black. Length to tip of the wings, about one-seventh of an inch. 



I follow Dr. Fitch in giving these as distinct, as he has described 

 them ; but I think it more than probable they are but varieties of ^. cary- 

 ella; possibly A. marginella may be distinct. 



The following species of this group are chiefly pests to the gardener 

 and farmer, often doing serious injury to the succulent vegetables of the 

 former and the grain of the latter : 



28. Aphis brassier, Linn. The Cabbage Plant-louse. 



This species was doubtless introduced from Europe at an early day, 

 and has spread over the country wherever cabbage is cultivated. It is 

 found not only on cabbage i)roper, but on the varieties of this useful 

 vegetable, and on the leaves of the ruta-baga, turnip, etc. As a general 

 rule, they do not require attention, but occasionally, in a season favorable 

 to their development, they become so numerous as to seriously affect the 

 growth of these vegetables. 



The wingless individuals, which are usually located in clusters, are 

 pale green and are dusted over with a fine gray powder ; their antennae 

 and legs are smoky or blackish, and in some individuals there is a row of 

 minute black dots along each side of the back. 



