234 
Journal of Agricultural Research 
Vol. I, No. 3 
the keeping of immature specimens of CalHephialtes messor in cold storage 
for a period of 14 months, after which they emerged without having suf¬ 
fered in the least. 
SEASONAL HISTORY 
The first females to emerge from hibernation in the spring of 1912 
appeared on May 3 and the last on May 15. These were placed with 
males in propagation cages. The first egg was deposited on May 13, ten 
days after the first emergence. 
In order to determine the maximum and minimum number of genera¬ 
tions in a season, the five earliest and five latest appearing female progeny 
of the hibernating brood were used in the life-history cages, a separate 
cage being used for each group. The same plan was followed out with 
each succeeding generation. From the earliest female progeny three 
complete generations were reared, and from the latest group two genera¬ 
tions were bred. With the hibernating brood this gives a maximum of 
four generations in the year and a minimum of three generations. Table 
X summarizes the data on the number of generations. It is interesting 
to note that the total time consumed by the three generations is only 
one day longer than that consumed by the two. 
Table X .—Number of generations of CalHephialtes sp. reared at Vienna, Va1912. 
Generation. 
Maximum number of 
generations. 
1 
Minimum number of j 
generations. ; 
Bate of first 
female. 
Total cycle. 
Date of last 
female. 
Total cycle. 
Days. 
Days . 
Hibernating. 
May 2 
Mav 
First. 
June 13 
41 
July 13 
61 
Second. 
July 18 
35 
Sept. 12 
61 
Third. 
Sept. 3 
47 
Total peri¬ 
od, days.. 
123 
122 
Average cycle, 
days. 
41 
61 
Development ceased at about 50° F., although oviposition was fre¬ 
quently carried on actively at that temperature. After the middle of 
October very few eggs hatched, although the last eggs of the season were 
not deposited until November 1. All but a very few of the larvae that 
hatched at this season passed through the feeding stage and constructed 
their cocoons. 
Calhephialtes sp. hibernates as a full-grown larva in its cocoon. In 
this stage it is capable of withstanding a very low temperature. The 
mortality among hibernating larvae during the winter of 1911-12 was 
very slight, if not nil, in spite of the fact that a temperature of —6° 
