Nature's Scavengers . 
159 
1876.] 
In how far the omnivorous rodents— -such as rats and 
mice — may be regarded as scavengers is somewhat doubtful. 
The best claim may be made for the grey or Norway rat 
(Hanoverian rat of Waterton), who is very fond of taking 
up his abode on the premises of knackers, bone-boilers, &c., 
and sometimes succeeds in penetrating into family vaults 
for the purpose of gnawing human remains. The black rat 
and the common mouse may occasionally devour putrid 
animal matter under the pressure of scarcity, but it by no 
means forms their ordinary or favourite diet. Still, animals 
of this tribe are, at the best, very unacceptable scavengers, 
from considerations which will be fully detailed when we 
come to speak of carrion-flies. 
Among birds we find two distindt main groups of carrion- 
eaters — the vultures and the crows. Both execute their task 
in exactly the same manner as the Canidse. They exhale 
from their skins the same detestable odour, and their dung 
is offensive in the extreme ; but as they are not given to 
injure man — either in his person or to any appreciable extent 
in his property — -they are, as scavengers, far superior to 
wolves, jackals, hysenas, panthers, and rats, and they may 
justly claim immunity from persecution, or even positive 
protection. Another bird, though very promiscuous in its 
diet, has some title to be regarded as a scavenger : we refer 
to the domestic duck, which will feast greedily upon putrid 
matter, the remains of its own kindred not excluded. Even 
tumours, the dressings from ulcers, and other the foulest 
rejectamenta of hospitals, are not disdained by these birds, 
which yet, in England, serve for the very type of all that 
is delicate. 
Among reptiles we are unable to point out any species of 
scavenging habits. Although the great majority of lizards 
and serpents are purely carnivorous, they seek invariably 
living prey. This the writer was able to establish most con- 
clusively, as far at least as European species are concerned, 
by a long series of observations made upon a numerous 
colony of these creatures, confined in a pit somewhat resem- 
bling a melon-frame, but filled with peaty earth, stones, and 
bushes of heath and of Ledum palustre. Small dead animals, 
such as mice, shrews, small birds, &c., if thrown into the 
pit, were completely disregarded by the snakes ; but if a 
live mouse was thrown in, all the venomous inmates were 
up in arms in a moment, until one of their number had 
given the fatal bite. On one occasion only a large male 
viper, who had been very restless for some days, was ob- 
served carrying a limb of a dead bird about in his mouth ; 
