512 THE MECHANICAL FUNCTIONS. 



its developement is usually carried farther, the 

 new stem being both thicker and longer, and 

 the branches wider and more numerous. The 

 antler of each successive year has, consequently, 

 a different form from that of the preceding ; and 

 when the animal has attained a certain age, the 

 extremities of the branches present broad ex- 

 pansions of bone, which the antlers of an earlier 

 growth had never exhibited. 



The short bony processes which extend in a 

 perpendicular direction on the head of the 

 cameleopard, are analogous, in some of the cir- 

 cumstances of their formation, to the antlers of 

 the deer, being of an osseous nature, and con- 

 tinuous with the frontal bone : but in other 

 respects they are very different; for instead of 

 being annually shed, they remain through life, 

 and continue to be covered with the integu- 

 ments, which retain, at the extremities, a tuft of 

 hair. The developement of these processes in 

 the young animal takes place in the same man- 

 ner as that of an antler, but it reaches only to a 

 certain point, upon attaining which the gi'owth 

 is arrested, and never proceeds farther. The 

 arteries cease to deposit superabundant nourish- 

 ment, but continue to maintain an exact equili- 

 brium between the expenditure and the supply ; 

 so that the horns of the cameleopard are never 

 shed, and remain permanent bony structures. 



A further modification of this process occurs 



