116 
PRELIMINARY LIST 
Fort Col]in«!, July 12th, on Popiilus monilifera, forming a 
pseudo gall by causing the upper surfaces of the leaf to fold 
together along the midrib(Co\\ en). 
Peinphigns popiili-iiionilis liiley and MonelL 
In Colorado, on narrow leaved cottonwood (Kiley and Monell, 1). 
Fort Collins, July 17th, in typical moniliform galls on 
leaves of Populus angustifolia; Hotchkiss, Delta County, 
July 14th, on the same host plant. Only one individual wasi 
found in each gall (Cowen). 
Pemphigus populi-raimiloriiiu liiley and Monell. 
On Populus balsamifera, Colorado (liiley—see liiley and Monell, 1). 
Fort Collins, July 12th, on Populus monilifera, in galls at 
base of petiole and on twigs. Sometimes the galls of this 
species are far enough up the petiole to be almost distinct 
from the twig, and are then quite similar to those of 1\ 
populi-tra ns versus (Cowen). 
Pemphigus populi-transversus liiley and Monell. 
On Populus monilifera and P. balsamifera, Colorado (Riley-see Riley and 
and Monell, 1). 
Fort Collins, July 12th, in typirnl galls with transverse 
openings, on petioles of Populus monilifera (Cowen). 
Pemphigus vagabuiidus Walsh. 
Fort Collins, galls on Populus (Blinn). 
Colopha ulmicola Fitch. 
Fort Collins, July 8th, in ‘‘cockscomb’’ galls on ITlmu^ 
americana. Five of the specimens examined have the 
cubital vein of fore wings simple (Cowen). 
Schizoneura americana Riley. 
Fort Collins, June 17th, on ITlmus americana (Cowen). 
Schizoneura lanigera llausm. 
Boulder, Denver, Canon City, Delta, and Brand Junction, 
on apple, common (Gillette). Hotchkiss, Delta County, 
August 23d, on young shoots of crab-apple (Cowen). 
Schizoneura querei Fitch. 
“Wingless form: Largest a liitle over 1 mm. long, very wooly, uniformly pale green, 
except eyes which are red, and black tip of beali. Beak reacliing slightly beyond second 
