850 
Journal of Agricultural Research 
Yol. XXX, No. 9 
brought into our ports in cargoes. 
Records in the Bureau of Entomology 
show that it has arrived in cargoes in 
fish “guano” and bone meal from 
Honolulu, in garlic from New Zealand 
(probably having developed in other 
material), in coconuts from Manila, in 
bones from Argentina, in copra from 
the Philippines, in palm-nut kernels 
from British West Africa and Liberia, 
in herring and whale “guano” from 
Scandinavia, in dried egg yolk from 
China, in coconut palm from Ceylon, 
and in rattan from Japan. In bone 
storages it is frequently found in com¬ 
pany with a closely related but eco¬ 
nomically unimportant species, Necro¬ 
bia ruficollis Fab. 
In the United States, as shown in 
Figure 1, reports indicate that most of 
the injury occurs in the Middle Atlantic 
States and that it is particularly 
marked in Virginia. Possibly this is 
due in a measure to the long storage 
of stocks of “Virginia” hams, which 
are not considered prime until they 
are about a year old. 
SUBSTANCES INJURED 
The first record of injury to human 
food by Necrobia rufipes seems to be 
that of Glover (13, p. 97-98), who 
reported it on cheese in Maryland. 
Riley (24) gave the earliest account of 
extensive injury to cured meats, con¬ 
cluding that attacks occur particularly 
to hams injured by overheating or by 
exposure to sun and rain. The species, 
he believed, is attracted by the fatty 
slime on hams. 
Our chief concern in this country is 
with the infestation of smoked pork, 
other materials being attacked only on 
rare occasions. 
The following list summarizes the 
known foods of this insect. The “sub¬ 
stances infested but not fed upon” are 
sought by the migrating, full-fed larvae 
as suitable materials in which to pupate. 
Baled cotton and wool are sometimes 
badly matted with the pupal cells of 
the insect when these goods are carried 
in the same ship with bones. 
Foods of the larvae or adults of the 
ham beetle, as recorded from literature, 
include: Cheese (25, p. 226; 31, p. 266), 
hams, bones (34, p. 161; 31, p. 266), 
fish (25, p. 226; 31, p . 266), drying 
carrion (31, p. 266), copra (10, p. 26; 2), 
hides (5), salt fish (7), bacon, dried egg 
(29), dried figs (17), and Egyptian 
mummies. 5 Bureau of Entomology 
records include: Dried egg yolk, hams, 
cheese, fish “guano” 6 , bone meal, 
bacon, copra, bones, palm-nut kernels, 
and herring and whale “guano.” 6 
Substances infested but not fed upon, as 
recorded in published accounts, include: 
Silk (28, p. 436), baled cotton (21), and 
woolen tops (11 ); rattan and salt are 
given in the files of the bureau. A 
number of other references to litera¬ 
ture, for the most part dealing with 
infestations of copra, are not included. 
NATURE OF INJURY 
Both larvae and adults feed upon 
smoked meats, the latter superficially. 
The larvae at first burrow beneath the 
hide, later extending their feeding 
deeper into the meat, chiefly in the fat 
portions (pi. 2, C). Frass is ex¬ 
truded from the burrows; this is shown 
in Plate 2, F. A piece of meat which 
had been seriously damaged on the 
flesh side is illustrated in Plate 2, A, 
and the work of the larvae in perforat¬ 
ing a grease-soaked paper wrapping is 
shown in Plate 2, E. Plate 2, B shows 
the work of this species in old cheese. 
BIOLOGICAL INFORMATION RE¬ 
CORDED BY OTHER WRITERS 
The life history and habits of Necro¬ 
bia rufipes have received little atten¬ 
tion. Riley (24) stated that hiberna¬ 
tion takes place solely as the larva and 
that no adults emerge before the first of 
May. On the other hand, Fay (8, p. 
197) listed it among insects secured in 
winter collections. 
5 See reference to Hope on Necrobia mumiarum, under “Synonymy.” 
6 Refuse used as fertilizer. 
EXPLANATORY LEGEND FOR PLATE 2 
Necrobia rufipes 
A. —Longitudinal section of an old infested ham. In this case most of the feeding has been on the inside 
and has extended toward the skin side. Burrows may be seen penetrating the solid fat. Extensive 
feeding took place under the skin at the shank end, some of which is shown in the photograph 
B. —Injured cheese. Several pupal cells are present in the excavated area. The dark spots are the excre¬ 
ment of the adult beetles. In this case the beetles and their larvae superseded an infestation of the 
cheese skipper (Piophila casei ) 
C. —Feeding burrows of larvae in the fat of an old ham. The cut surface, to the right of the black ink line, 
slants down into the tissues 
D. —Pupal cells formed in creases of paper wrapper on ham. Cells torn open when paper was flattened 
out 
E. —An old ham which had been wrapped for several months. The inner paper had become grease-soaked 
and the larvae penetrated it in the course of their feeding 
F. —‘An old shoulder infested with larvae, showing the mealy frass from their burrows which has accumu¬ 
lated on the surface 
