196 
IOWA ACADEMY OF SCIENCE Vor. XXIX, 1922 
stage, although an occasional adult and a few young nymphs 
were seen. Again September 7, 1910, all stages Vere present. 
They were abundant throughout September and on October 1 
most of the insects were in the older nymphal stages. By October 
24, practically only the adults were present. 
These notes were taken at random and no "very definite state- 
ment can be made regarding the number of generations. How- 
Fig. 1. S'urface of leaf, showing egg beneath. 
ever, there are at least two generations in the latitude of central 
Iowa. Hawley (1918) reports that in New York state two gen- 
erations occur, with a probable third generation in dry seasons. 
The egg. — The eggs were found in the leaves of the hop-tree 
and their location was readily observed on the lower surface, 
apparently having been deposited from that side. The outline 
of the egg, as seen from the exterior, resembles that of the oyster 
shell scale, Lepidosaphes ulmi h. The eggs themselves are ellip- 
tico-cylindrical ; white in color. A single egg exposed from the 
Fig. 2. Leaf tissue cut away exposing the egg. 
