Journal of Agricultural Research 
Vol. XXX, No. 9 
862 
active and predatory; their habit of 
infesting smoked pork has probably 
been acquired rather recently. The 
larvae are responsible for most of the 
damage to infested meats. They bore 
holes in the meat, preferably burrowing 
In warm weather the incubation period 
is four days or more. The preovi- 
position period is as brief as two days. 
The period from hatching of the egg 
to adult emergence may be as short 
as 30 days, including 17 days as grow- 
Table VIII. — Cocoon period of Necrobia rufipes , 1922 
Cocoon 
formed 
Prepupal 
period in 
cocoon ° 
Pupal 
period 
Cocoon 
period 
Average 
tempera¬ 
ture 
during 
cocoon 
period 
Cocoon 
formed 
Prepupal 
period in 
cocoon a 
Pupal 
period 
Cocoon 
period 
Average 
tempera¬ 
ture 
during 
cocoon 
period 
Days 
Days 
Days 
°p 
Days 
Days 
Days 
O F 
Jan. 17 
_ 
42 
67 
Aug. 21 
17 
4 
21 
76 
17 
46 
67 
21 
10 
12 
22 
76 
17 
55 
67 
21 
9 
14 
23 
76 
18 
51 
67 
21 
15 
8 
23 
76 
19 
45 
67 
21 
8 
18 
26 
76 
20 
47 
67 
21 
5 
22 
27 
76 
20 
55 
67 
21 
9 
34 
43 
73 
21 
41 
67 
21 
26 
54 
80 
71 
21 
47 
67 
22 
10 
10 
20 
76 
22 
40 
67 
22 
17 
31 
48 
73 
22 
52 
67 
23 
16 
4 
20 
77 
24 
36 
67 
23 
16 
6 
22 
76 
24 
42 
67 
23 
14 
10 
24 
76 
24 
44 
67 
! 23 
14 
10 
24 
76 
24 
45 
67 
23 
14 
12 
26 
76 
24 
46 
67 
23 
16 
12 
28 
75 
24 
49 
67 
24 
13 
5 
18 
76 
26 
46 
67 
24 
15 
8 
23 
76 
27 
41 
67 
24 
14 
9 
23 
76 
28 
. 
41 
67 
24 
13 
12 
25 
76 
28 
58 
67 
24 
13 
13 
26 
76 
Feb. 4 
46 
66 
24 
15 
15 
30 
75 
Mar. 25 
32 
69 
24 
19 
23 
42 
73 
25 
14 
21 
35 
69 
1 24 
17 
27 
44 
73 
26 
12 
21 
33 
69 
25 
14 
8 
22 
76 
26 
12 
28 
40 
69 
i 25 
15 
7 
22 
76 
27 
12 
21 
33 
69 
25 
13 
9 
22 
76 
28 
12 
24 
36 
69 
i 26 
13 
8 
21 
76 
31 
10 
21 
31 
69 
: 26 
12 
15 
27 
75 
Apr. 1 
10 
22 
32 
69 
; 26 
15 
13 
28 
75 
3 
9 
24 
33 
70 
! 28 
9 
10 
19 
76 
9 
9 
21 
30 
70 
28 
9 
13 
22 
76 
Aug. 14 
7 
4 
11 
77 
! 28 
13 
11 
24 
75 
15 
4 
9 
13 
77 
28 
12 
30 
42 
73 
15 
9 
12 
21 
76 
29 
8 
10 
18 
77 
15 
10 
11 
21 
76 
Sept. 1 
10 
8 
18 
76 
15 
14 
8 
22 
76 
i 2 
6 
8 
14 
77 
16 
6 
11 
17 
76 
2 
8 
22 
30 
73 
16 
9 
12 
21 
76 
1 2 
9 
23 
32 
73 
16 
13 
9 
22 
76 
| 5 
6 
9 
15 
75 
16 
12 
11 
23 
77 
5 
6 
21 
27 
72 
17 
11 
5 
16 
76 
1 5 
6 
21 
27 
72 
17 
11 
9 
20 
76 
6 
14 
13 
27 
72 
17 
11 
9 
20 
76 
! 14 
22 
12 
34 
70 
19 
8 
11 
19 
76 
14 
17 
19 
36 
70 
19 
8 
14 
22 
76 
i 16 
15 
15 
30 
70 
19 
17 
7 
24 
76 
16 
14 
18 
32 
70 
19 
19 
9 
28 
76 
16 
21 
11 
32 
70 
19 
17 
11 
28 
76 
16 
16 
19 
35 
69 
21 
15 
5 
20 
76 
16 
32 
22 
54 
68 
21 
10 
11 
21 
76 
a The prepupal period (period from formation of cocoon to appearance of pupa) and pupal period 
occurring in cocoons formed Aug. 14, et. seq., were determined by opening the cocoons. Prior to Aug. 
14 the same notations were made by observations through the glass of vials containing cocoons built 
against the glass. 
into the fat parts. The adults feed 
chiefly on the surface. Pupation occurs 
within a white cocoon constructed with 
drops of froth emitted from the mouth 
of the larva. 
The adult may live for more than 
14 months, the female depositing as 
many as 2,100 eggs during that time. 
ing larva and 13 days within the co¬ 
coon. 
An important consideration in the pre¬ 
vention of injury by the ham beetle is 
the caref ul wrapping of meats. Probably 
the most effective method for the erad¬ 
ication of an infestation is a thorough 
fumigation with hydrocyanic acid gas. 
