90 
BULLETIN 1476, U. S. DEPARTMENT OF AGRICULTURE 
In the spring of 1921 a total of 100 overwintering larvae were 
caged at Silver Creek, N. Y., for pupation records. From this mate- 
rial a total of 14 females and 19 males were reared, the pupal period 
of the females averaging 10.93 days and for the males 11.26 days. 
Table 26 gives the available records of the duration of life-history 
stages which were taken at Scotia, N. Y., during the seasons of 1920 
and 1921. 
OHIO 
Table 27 gives a summary of the available records relative to 
the duration of life-historv stages at Sandusky, Ohio, during 1923 
and 1924. 
Table 27. — Duration of Pyrausta nuoilalis stages at Sandusky, Ohio 
1923 
1924 
Average 
in days 
Number 
of speci- 
mens 
Average in 
days 
Number 
of speci- 
mens 
5.04 
4,801 
5.58 
17, 693 
Larval period: 
First instar . 
4.32 
4.56 
4.80 
17.94 
8.83 
100 
Second instar . . .. h ._ 
100 
Third instar .... . ' 
100 
Fourth instar . . ..... __| 
100 
Fifth instar 
24 
Total days to last molt 2 . ...... . 
2 21. 6 to 30. 5 
Pupal period: 
Female.. 
Male 
12.41 
12.39 
39 
46 
12.12 
13.25 
16 
20 
Adult stages: 
Preovi position ... ... .. ... _. 
2.79 
6.46 
1.50 
9.60 
12.40 
24 
24 
24 
25 
34 
3.68 
14.85 
2.59 
19.70 
22.50 
47 
Ovi position 
Postoviposition 
Longevity? .. . ... .. 
47 
47 
50 
Longevity c? 
78 
i See footnote 1, Table 25. 
2 Not including indefinite duration of last instar. 
The records pertaining to incubation and adult stages which appear 
in Table 27 were obtained by confining 25 pairs of adults in the 
1923 series and 50 pairs of adults in the 1924 series, together with 
extra males in some of the cages. In the 1923 series one female and 
in the 1924 series three females did not deposit eggs. The averages 
for adult stages, except longevity, are based upon the number of 
females which deposited eggs. 
LARVAL HABITS 
HATCHING 
About a day before hatching takes place the black eye spots and 
reddish mandible tips of the developing larva become discernible 
through the semi-transparent chorion of the egg. A few hours be- 
fore hatching the head and thoracic shield become black and assume 
a central position in the egg. The body segmentation and the black 
spines on the body of the larva are also plainly discernible before 
