1952] 
Feldman and Bailey — Corythucha 
101 
0.49-0.52 mm. and its average length is 0.51 mm. Valve 
two has an average length of 0.45 mm. and its range of 
variation is 0.44-0.47 mm. The shape of this valve is 
elongate and its anterior lateral margins are rounded 
(fig. 16). The subgenital plate is elliptical. 
C. juglandis (Fitch) 
The length of valve one varies from 0.47-0.53 mm. 
and its average length is 0.49 mm. Valve two ranges from 
0.42-0.47 mm. and its average length is 0.45 mm. The 
latter valve is elongate and its anterior lateral margins are 
pointed. The subgenital plate is elliptical. 
C. marmorata (Uhler) 
On the average, valve one measures 0.39 mm. and 
its range of variation extends from 0.36-0.41 mm. The 
shape of this valve in lateral view is unique (fig. 2). Valve 
two presents an interesting configuration which by itself 
is highly diagnostic. The anterior halves of these valves 
together form a shape not unlike that of a mushroom 
(fig. 8). The average length of the second valves is 0.32 
mm. and it varies from 0.30-0.32 mm. The subgenital 
plate is much broader than long. 
C. mollicula Osborn and Drake 
Valve one has an average length of 0.31 mm. and 
its range of variation is 0.29-0.34 mm. The shapes of 
valves one and two are identical to those of C. arcuata 
(fig. 5). Valve two measures on the average 0.26 mm. and 
its variation ranges from 0.23-0.28 mm. The subgenital 
plate is circular. 
C. pallipes Parshley 
Valve one varies in length from 0.52-0.54 mm. and 
its average length is 0.54 mm. Valve two varies from 0.47- 
0.52 mm. and the average measurement is 0.49 mm. The 
subgenital plate is elliptical. 
C. pergandei Heidemann 
Valve one varies from 0.44-0.50 mm. with an average 
length of 0.47 mm. The shape of the distal end of this 
valve is abruptly pointed (fig. 1) . Valve two is elongate and 
tapers posteriorly (fig. 14). Its measurements vary from 
0.37-0.45 mm. and its average length is 0.41 mm. The sub- 
genital plate is elliptical. 
