THE EUROPEAN ELM SCALE IN THE WEST. 9 
of trilocular pores (Pl. III, /'). These are presumably what produce the wax - 
filaments on some males. 
There are two forms of the male, winged and wingless. The winged form 
(Pl. Il, D) has full-sized wings folded over the dorsum when not in use, while 
the wingless form (PI. II, C) has only short wing pads. The body of the wing- 
less form is occasionally broader than that of the winged. There are, moreover, 
~ all grades between these two extremes, having all sizes of malformed wings. 
Two wax filaments, borne on the anal lobes, extend posteriorly and equal the 
length of the body in perfect males. These also vary in length, however, and 
_ may be present or entirely lacking on either the winged or wingless forms. 
LIFE HISTORY AND HABITS. 
In the spring after mating the female scales are found to con- 
tain a few eggs. By the time “they have completed their semicocoons, 
_ however, they are well filled with eggs and have increased consid- 
erably in size. 
OVIPOSITION. 
The eggs remain in the body of the adult female until the embryos 
are about to hatch. As each embryo becomes fully developed the 
egg is expelled ventrally from near the tip of the abdomen. They 
are thus laid in a sort of pocket, being protected by the body of the 
mother and the surrounding fringe of wax. 
Each female is capable of laying a large number of eggs. Adults ex- 
— amined on July 5, 1919, after having laid for some time, contained from 
_ 97 to 138 eggs. Professor Doten, of Nevada, reports having counted 
_ 60 to nearly 300 dead larvee, which had been unable to escape from 
under different females. A drawing of the ovaries of an adult 
female by R. E. Snodgrass (20, fig. 19), would indicate a still larger 
number. He figures over 200 on one branch of the oviduct making 
a total of approximately 425 eggs from one female. This would 
indicate that the rate of increase is quite large, yet not as great as 
that of many other scale insects. 
The eggs are laid slowly, covering a considerable period of time, 
and only during the warm part of the day. One female observed 
laid 16 eggs in 54 hours, or 1 about every 20 minutes. The larve 
hatch from these eggs ¢ honk 40 minutes later and are ready to crawl 
away in another half hour. 
It has several times been reported that the adult females give 
birth to living young. These misstatements are probably due to the 
- fact that the eggs hatched very soon after deposition and were not 
seen by these observers. 
LARV. 
Newly hatched larve are active and soon seek a place for attach- 
ment. Some attach themselves to twigs and branches, while a large 
majority of them migrate to the leave es, where they settle on both 
the upper and lower surfaces along the midribs, the aa ence of 
the leaf-veins affording them some protection. (Pl. V, 4.) They 
remain in these positions until fall. By this time ine are second- 
stage larve, having undergone their first molt about six weeks after 
hatching. 7 
