1896.] Fossils and Fossilization. 999 
appear that any wide-spread catastrophes killing large num- 
bers of a herd are rare, and in the case of individual deaths, 
.the remains, if carried by freshets to some lower level, would 
seldom undergo the same vicissitudes and be buried at the 
same point. Yet the wholesale destruction of mammals in a 
state of nature may be considered a possibility, though im- 
probable. Sir Samuel H. Baker speaks” of cattle introduced 
at his camp at Fatiko,in Africa, who could not live there, “ as 
the herbage was quite different to that to which they had been 
accustomed.” They died so rapidly and in such numbers that 
in three months only three or four remained out of as many 
thousand. In the over stocked ranches of California, thous- 
ands of heads of sheep have been seen lying dead in vast 
heaps in ravines and valleys, as if nourishment had become 
exhausted by draughtor by actual deplenishment of the avail- 
able pasturage. Is not asimilar mortality possible under nat- 
ural conditions when, as in the case of the Fatiko cattle, ani- 
mals have been driven by storms into localities incapable of 
their support, or when, as with the ranch sheep of California, 
an area previously put under severe strain for the support of 
its feral population, by an accident of weather or season fails 
entirely to furnish its occupants with food ? 
Wallace in his Malay Archipelago speaks of the destructive 
effects of drought upon animal life in the Arne Islands, where 
from an excessive scarcity of water, “sometimes hundreds of 
birds and other animals die.” The effects of sudden and vio- 
lent falls of hail and snow are noticed by Stansbury, who 
found on the shores of the Great Salt Lake, a large number of 
young pelicans killed by the severity of a hail storm. The 
possibility of numbers of animals becoming buried at once, 
may be illustrated in the condition of the banks of the River 
Vaal in South Africa, of which Dr. Holub says that “its 
banks almost to the very middle of the channel are so soft and 
slippery, that draught animals going to drink are liable to 
sink so deep into the mud that it is impossible to extricate 
them.” The internecine strife of wild animals may itself 
result in the accidental death of numbers, as when the hunters 
10 Ismailia, Sir S. H. Baker. p. 294. 
