1 8 EXTINCT MONSTERS. 



found collected together the bodies of 9 black cattle, 3 horses, 

 1840 sheep, 45 dogs, 180 hares, together with those of many 

 smaller animals, also the corpses of two men and one woman. 



Humboldt, the celebrated traveller, says that when, at certain 

 seasons, the large rivers of South America are swollen by heavy 

 rains, great numbers of quadrupeds are drowned every year. 

 Troops of wild horses that graze in the "savannahs," or grassy 

 plains, are said to be swept away in thousands. 



In Java, in the year 1699, the Batavian River was flooded 

 during an earthquake, and drowned buffaloes, tigers, rhinoceroses, 

 deer, apes, crocodiles, and other wild beasts, which were brought 

 down to the coast by the current. 



In tropical countries, where very heavy rains fall at times, and 

 rivers become rapidly swollen, floods are a great source of danger 

 to man and beast. Probably the greater number of the bodies 

 of animals thus drowned find their way into lakes, through 

 which rivers flow, and never reach the sea ; and if the growth of 

 sediment in such lakes goes on fairly rapidly, their remains may 

 be buried up, and so preserved. But in many cases the bones 

 fall one by one from the floating carcase, and so may in that way 

 be scattered at random over the bottom of the lake, or the bed 

 of a river at its mouth. In hot countries such bodies, on reach- 

 ing the sea, run a great chance of being instantly devoured by 

 sharks, alligators, and other carnivorous animals. But during 

 very heavy floods, the waters that reach the sea are so heavily 

 laden with mud, that these predaceous animals are obliged to retire 

 to some place where the waters are clear, so that at such times 

 the dead bodies are more likely to escape their ravages; and, at 

 the same time, the mud with which the waters are charged falls 

 so rapidly that it may quickly cover them up. We shall find 

 further on that this explanation probably applies to the case of 

 the "fish-lizards," whose remains are found in the Lias formation 

 (seep. 51). 



But, for several reasons, sedimentary rocks formed in lakes 



