MODE OF PROGRESSION 



the increased size of those remaining. But, unlike 

 the camel, one toe is much larger than the other, 

 and they are widely separated. In both cases the 

 structure of the foot is designed to prevent the 

 animals from sinking into the sand.^ 



In this connection it is interesting to note that the 

 natural walk of the camel is an "amble," in which 

 two feet on the same side are brought forward and set 

 down together at the same time. This is a method 

 of progression very rarely seen, and though sometimes 

 used by a horse, it is an artificial pace and has to be 

 taueht to him. Since the two feet are set down 

 together the weight of the body is more evenly 

 distributed, and this fact again tends to prevent the 

 animal from sinking too deep into the yielding surface 

 on which it walks. 



The female carries her young for eleven months, 

 and produces only one at a birth. These young 

 camels attain a height of 3 feet within eight days, 

 but are not full grown until the fifteenth or sixteenth 

 year. They are covered with soft silky hair, which is 

 most profuse along the back, and in appearance are 

 extremely ungainly. 



Before Sfoino- on to describe the greneral character- 

 istics of the camel, it may be of interest to note how 

 camels were introduced into the United States in an 

 attempt to overcome the difficulties of crossing the 

 arid and waterless plains of Arizona and parts of 

 California, previous to the building of the railways. 

 In 1855 the War Department of the United States 

 imported from Asia Minor a number of camels. 



^ For further particulars regarding the structure of the camel, see 

 The Natural History of Animals, by J. R. A. Davis, vol. iii. 169, vol. 

 V. 152, and vol. vii. 231. 



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