9 6 



DOMESTICATED ANIMALS 



peculiar advantage that it is on the average as large as the 

 horse, is nearly as quick-footed when walking, and has at the 

 same time a considerable share of the patient endurance to 

 hard labor and scant fare which characterizes the donkeys. 

 It matures somewhat more speedily than its nobler kinsman, 

 being ready to meet severe strains perhaps a year earlier. 



Unless unconscionably abused, its period of fitness for hard 

 work endures about one-third longer, often lasting for thirty 

 years. It is singularly exempt from disease, its sturdy 

 frame withstanding rude usage until the old age time. 



The mule is especially interesting to the naturalist for the 

 reason that it affords the only certain case in which a hybrid 

 has proved decidedly serviceable to man. It is not unlikely 

 that a similar mixture of the blood of two species occurs in 

 our ordinary cats, and it may exist in the case of the dog 



