198 Life-histories of Northern Animals 



joint. It was so violent that it jarred the hand laid on it. It 

 was deep-seated and on the level of the cloots or back hoofs. 

 Apparently it was made by tendons or sesamoids slipping over 

 adjoining bones. 



The object of this curious sound is, doubtless, the same 

 as that of the whistling of a whistler's wing or the twittering 

 of birds migrating by night. It is to let the rest know what is 

 doing — that the band is up and moving — has gone such and 

 such a way, or to notify the little one that his mother is on the 

 march and that he should keep alongside. 



HOOFS The hoof of this animal has another claim on attention. 



As noted in the Moose article, nature has two answers 

 for the problem of travel through deep snow, namely, stilts 

 and snow-shoes. These are exemplified, respectively, by the 

 feet of the Moose and the feet of the Lynx. Both contriv- 

 ances are good, but, upon the whole, the latter is the better. 

 In the Caribou we have a wonderful combination of the 

 two. Nature has given to this creature of snow and swamp 

 both stilts and snow-shoes. Its long, thin shanks are actually 

 longer in proportion to its bulk than are those of the Moose, 

 and its hoofs are a unique combination of snow-shoes and 

 skates. 



The ordinary track of a moving Reindeer I found to be 

 4 inches wide by 7 long. In places it spreads an inch wider 

 and a couple of inches longer. As the need is increased the 

 bearing surface is increased by bringing more of the foot to the 

 ground. So that in crossing bogs or deep snow the whole leg 

 from hoof to hock gives supporting surface. I noticed that 

 in crossing snow-drifts I sunk much deeper than the Rein- 

 deer. I found, further, that a Reindeer has about i square 

 inch of foot support for each 2 pounds of his weight, while 

 the Moose in standing is under a pressure of 8 pounds to the 

 square inch. 



Captain Hardy states," concerning the Caribou, "that its 

 foot is a beautiful adaptation to the snow-covered country in 



" Forest Life in Acadie, 1869, pp. 129-130. 



