1906 ENTOMOLOGICAL SOCIETY. 



HacTcdberry Nipple Gall (Pachypsylla c eltddis -mammae J . 



A woody gall with bluntly rounded apex and slightly constricted at the 

 point of attachment to the leaf. It is found on the underside of the leaf 

 and opposite the gall is a concave depression. Occurs on Hackberry (Celtis 

 occidentalis). Common. 



Hackherry Blister Gall {Pachypsylla celtidis-vesiculum). 

 Circular spot-like galls on the under side of the leaf with a small nipple 

 in the middle. Occurs on Hackberry {Celtis occidentalis). Common. 



Sumac Tomato Gall {Pemphigus rhois). 

 Large, smooth, rounded galls, somewhat resembling a tomato in shape. 

 Yellowish green in color and sometimes tinged with red. The interior is 

 hollow and filled with lice. Occurs on Sumac {Rhus typhina). Common. 



Woolly Aphis Gall of Elm. 



The lice may be seen in large clusters on the trunk and branches of the 

 tree. They suck the juices from the bark and cause knot-like swellings to 

 appear. These galls sometimes attain a diameter of two or three inches. 

 Occurs on many species of Elm {Ulmus sp.). The one from which this gall 

 was described was a young American Elm {Ulmus Am,ericana). Common. 



Woolly Aphis of Apple. 

 This species of woolly aphis live in small colonies and produce small 



swellings on the young twigs. The galls often become twice the diameter 

 of the stem upon which they are feeding. Occurs on Apple {Pyrus malus). 

 Common. 



Grape Phylloxera {Phylloxera vastatrix). 



Small galls on either upper or lower surface of the leaf. Another gene- 

 ration of this insect forms galls upon the roots, and it is in this stage that 

 it causes considerable destruction among the cultivated varieties. Occurs 

 on wild and cultivated Grapes. Very common on Wild Grape (Vitis vulpina). 



Lepidoptera. 

 Elliptical Goldenrod Gall {Gelechia gallaesolidaginis) . 

 A large elongated stem gall. It is about one inch in length and mono- 

 thalamous. The larval chamber is quite large. It remains over winter in 

 the pupal stage and the imago emerges in the spring. Occurs on Goldenrod 

 {Solidago sp.). Common. 



7'he Locust-Twig Borer {Ecdytolopha insiticiana) . 

 Oval swellings on the branches and twigs, , varying from 2-4 cm. in 

 length and about a cm. in thickness. Generally occurring at the junction 

 of the leaf petiole with the branch, about which point the wood is destroyed 

 and a mass of castings and sawdust surrounds the hole entering the gall. 

 The tunnel of the gall maker runs some distance, and at the bottom of it 

 is a reddish-brown larva about half an inch in length with a light-brown 

 head. 



COLEOPTERA. 



Willow Branch Gall {Saperda concolor). 

 Large, rough galls on the stems of the willow and cottonwood. The 

 galls are smooth at first, but become rough later in the season. The affected 

 portions are very weak and easily broken off by the wind. Occurs on Wil- 

 lows and Cottonwood. Common. 



5 EN. 



