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6 .. BULLETIN 416, U. S. DEPARTMENT OF AGRICULTURE. ; 
ondary nymph or deutonymph. The activities of the deutonymph 
are very similar to those of the protonymph and the duration of the 
stage is about equal to the time required by the latter. Thethird molt 
gives issue to the female. The single nymphal stage of the male 
exhibits the same biologic activities as do nymphs of the female. 
The time required for this stage, however, is a trifle longer than that 
consumed by the female primary nymphal stage, yet slightly shorter 
than the combined periods of the two nymphal stages. In summer 
the female requires, usually, about 10 or 11 days for the completion — 
of a generation, while the male requires about 9 or 10 days. 
During the course of the year, in the latitude of Batesburg, S. C., 
there are ordinarily 16 or 17 generations, whereas in cooler portions — 
of the. United States, naturally, there are fewer broods. In the 
South the red spider passes the winter chiefly in the adult stage, and 
even propagates considerably at a temperature slightly above freezing. 
Feeding continues intermittently on several species of plants which 
bear leaves throughout the winter season. ° 
DESCRIPTION AND HABITS. 
THE EGG. 
Description.—The eggs (Pl. LI, fig. 1) are almost perfect spheres. 
When first deposited they are about as clear as water, but as incuba- 
tion progresses they become opaque, turning a dark straw color — 
just before hatching. A series of spots becomes apparent, and in the 
later stages of incubation the carmine eyes of the embryo are visible 
through the shell. The eggs are deposited singly on the underside of 
the host leaf and directly on the surface unless copious webbing is 
present, in which case eggs are frequently attached to the fibrils 
slightly above the surface of the leaves. Although very minute in 
size, the eggs are relatively large as compared with the size of the 
female red spider. A series of measured eggs averaged 0.129 mm. in 
diameter. ; | 
Number laid.—The number of eggs deposited by a single female is 
subject to considerable variation, depending, apparently, on tem- 
perature, locality, and suitability of food, but observations show that 
practically all of the eggs hatch. Perkins in 1896 states that in 
Vermont the brood varies between 50 and 100 eggs, that oviposition | 
covers on an average about 7 days, and that the average daily deposi- 
tion is about 10 eggs. Worsham (1910) records 80 eggs as the average 
full brood in Georgia, with the daily deposition varymg from 1 to 12 
per day, and covering an oviposition period of from 6 to 10 days. 
He states that 94 eggs was the largest number recorded from a single 
female. Ewing (1914), working in Oregon, found that females 
averaged 41 eggs per brood, with 63 as the greatest number. His 
records show 9 eggs as the maximum deposition per day, with 1 as a 
