ON DESIGN IN ANIMAL BODIES, 



199 



period of its growth, the horn, c, has around it a 

 tender soft covering, full of vessels, and which is 



Section of the root of a deer's horn. 



necessary to its growth and support. But when 

 the horn has acquired its full form and strength, 

 this velvet covering is destroyed by a very curious 

 process. At the root of the horn, near the skull, 

 a circlet of tubercles, d, called the burr or pearl, 

 is found : the principal vessels run between these 

 tubercles, and, as the tubercles grow, they close 

 in upon the ascending blood-vessels, compress 

 them, and prevent their conveying blood to the 

 horn : then the membrane, which was vascular, 

 becomes insensible and dead, and in time is rub- 

 bed off. 



In old treatises on hunting, the separation of 



