WILD ANIMALS IN CAPTIVITY 



wear down, and unless they were reproduced and con- 

 tinually growing the animals would die from starvation. 



It is not my intention to enter into the anatomical 

 details of the very remarkable conditions and various forms 

 of teeth structure found in the animal world, but simply 

 to state facts, taking for example the teeth of the beaver. 

 This rodent's food consists of the bark of trees and other 

 vegetable substances, it will, however, sometimes gnaw 

 bones and horns. If by accident or otherwise one of the 

 four incisor teeth should be broken, the tooth on the 

 opposite jaw would continue to grow, and having nothing 

 to oppose its growth would become so elongated as to 

 cause the animal much difficulty in obtaining food ; in fact, 

 many rodents have been found dead from this cause. I 

 have from time to time been compelled, in order to save 

 the lives of the animals, to capture some of the beavers in 

 the Gardens and cut off the elongated incisor teeth. 



It happens unfortunately that, in order to prevent 

 animals of this class gnawing their way out of their 

 enclosures and making their escape, I am obliged to 

 employ iron, and they in attempting to bite and gnaw 

 this metal break their teeth, consequently in course of 

 time the opposing teeth become too long to be useful, and 

 therefore it is found necessary to cut them shorter to 

 make them even, so as to be used as before. This opera- 

 tion is by no means an easy one. In the first place, to 

 hold an animal of this strength and form is a very difficult 

 matter. I have found it necessary to confine the animal 

 in a strong net, two persons being required to hold it in 

 order to prevent it struggling. When this preliminary 

 business is arranged, the operation is gone through. The 

 enamel of the front of the incisor teeth is so excessively 

 hard that it requires a very sharp three-cornered steel file 

 to make any impression. As soon, however, as the enamel 



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