1038 
Journal of Agricultural Research 
Vol. XXXI, No. 11 
VAULT EXPERIMENTS 
Specimens of 20 species of insects were used in the experiments 
conducted in the concrete vault. They were confined in pill boxes or 
glass vials stoppered with cotton, and individuals of each species were 
placed on a ledge of an observation window so that their actions could 
be observed at all times. A vacuum of from 24 inches to 28 inches 
was maintained automatically throughout the experiment. The 
barometer reading for the period varied between 29.3 and 29.7 inches; 
the temperature varied between 60° and 70° F. At the end of three 
days specimens of all species of insects were removed and examined. 4 
Other specimens of all species were removed at the end of 4 days, 
5 days, 6 days, and 7 days, respectively. 
The data in Table III indicate that exposure to a vacuum varying 
from 24 to 28 inches for three days killed a large proportion of the 
insects. A very considerable number of the coleopterous larvae 
survived, only 20 per cent of those of Trogoderma tarsale being killed, 
and 60 per cent of those of Tenebrio obscurus. The softer-bodied 
larvae of Dermestes vulpinus and the lepidopterous larvae were killed. 
The adults which escaped belong to the small grain-infesting species, 
with the exception of adults of Alphitobius which are larger by 
comparison. 
Table III .—Effect of vacuum varying from 24 to 28 inches upon insects in a concrete 
vault containing 512 cubic feet 
Insect 
Killed in 
three days 
Killed in 
four days 
Killed in 
five days 
Killed in 
six days 
Killed in 
seven days 
03 
bfl 
tdO 
© 
a} 
> 
A 
s 
Pi 
P 
P4 
[ Adults 
8> 
be 
Larvae 
Pupae 
Adults 
m 
bo 
be 
H 
[ Larvae 
[ Pupae 
| Adults ] 
03 
ta 
to 
W 
| Larvae 
© 
03 
Pi 
£ 
Adults | 
03 
bfi 
te 
W 
| Larvae j 
Pupae 
Adults i 
P. 
P. 
P. 
P. 
P. 
P. 
P. 
P. 
P. 
P. 
P. 
P. 
P. 
P. 
p. 
P. 
P. 
P. 
P. 
P. 
ct. 
ct. 
ct. 
ct. 
ct. 
ct. 
ct. 
ct. 
ct. 
ct. 
ct. 
ct. 
ct. 
ct. 
ct. 
ct. 
ct. 
ct. 
ct. 
ct. 
Alphitobius piceus Oliv_ 
90 
86 
_ 
90 
_ 
86 
--- 
100 
96 
100 
_ 
98 
_ 
100 
_ ^ _ 
100 
Anthrenus fasciatus Hbst_ 
92 
155 
100 
100 
io5 
100 
100 
100 
100 
100 
100 
100 
100 
100 
100 
Attagenus piceus 01iv____ 
66 
100 
100 
78 
100 
100 
78 
100 
100 
80 
100 
100 
95 
100 
100 
Cryptolestes pusillus Schon 
100 
100 
100 
100 
100 
Dermestes vulpinus Fab_ 
100 
100 
100 
100 
100 
100 
100 
100 
100 
100 
Ephestia kuehniella Zell_ 
100 
155 
100 
100 
155 
100 
100 
155 
100 
100 
100 
100 
100 
Gnathocerus cornutus Fab_ 
90 
98 
100 
100 
100 
100 
___ 
100 
i55 
100 
100 
155 
100 
Gnathocerus maxillosus Fab 
90 
94 
100 
100 
100 
100 
'100 
100 
Necrobia rufipes De Geer_ 
100 
100 
100 
100 
100 
Oryzaephilus surinamensis L 
50 
65 
75 
90 
100 
Plodia interpunctella Hbn 
100 
100 
100 
100 
100 
Silvanus gemellatus Duv 
100 
100 
100 
100 
100 
Sitophilns oryza L 
100 
100 
100 
100 
100 
Sitophilus granarins L 
100 
100 
100 
100 
100 
Tenebrio obscurus Fab- 
60 
100 
60 
100 
80 
100 
80 
100 
___ 
§5 
100 
Tineola biselliella Hum _ 
ioo 
100 
155 
100 
155 
100 
155 
100 
155 
100 
155 
100 
155 
100 
I5o 
100 
100100 
i55 
100 
Tinea pellionella L__ 
100 
100 
100 
100 
100 
Tribolium confusum Duv 
98 
99 
100 
100 
100 
Tribolium ferrugineum Fab 
99 
100 
100 
100 
100 
Trogodema tarsale Melsh 
20 
20 
20 
30 
30 
The data indicate that exposure for 4, 5, 6, and 7 days did not kill 
all individuals. It is interesting to note that adults of Alphitobius 
piceus and Oryzaephilus surinamensis were not all killed by an ex¬ 
posure of 6 days (although the last ones succumbed on the seventh 
4 All treated specimens were held for two weeks after the experiment and were examined at frequent 
intervals to see if any would recover. 
