Natural History 475 



when there is only a small, permanent, skin-covered, bony out- 

 growth on the forehead, called the pedicle, which grows in girth 

 in subsequent years. In the second year there is an extra- 

 ordinarily rapid multiplication of bone-forming cells on the top 

 of the pedicle, and a short unbranched antler is formed, which 

 carries upwards the hot skin or "velvet." The blood-vessels in 

 the velvet supply the food which admits of the rapid growth 

 of the skin, and they also keep the growing antler tissue suitably 

 warm. The materials for the growth of the antler itself are 

 brought by internal blood-vessels from the pedicle or stalk. 

 Branches from the fifth brain-nerve run up the velvet and make 

 it exquisitely sensitive an adaptation that saves the stag from 

 knocking the still soft antlers against hard objects. 



In ordinary deer the antlers are as transient as the leaves of 

 the forest. They drop off and there is a new growth next year. 

 The second antler has a stem and one branch or tine, and a new 

 tine is added each successive year until the stag reaches maturity, 

 after which the antler growth becomes irregular. 



The shedding of the antlers is an extraordinary process. It 

 is prepared for from the start by automatic arrangements which 

 cut off the supply of blood from the velvet, obliterate the internal 

 blood-vessels, and form at the base a soft tissue which loosens the 

 organic connections between the dead antler and the living ped- 

 icle. The dying away of the base of the antler would be called 

 disease in other animals; it has become mysteriously regularised 

 in stags. The whole process is extraordinary; the growth of a 

 fine "head," perhaps 70 Ibs. in weight, takes place in three months 

 an expensive utilisation of material called into activity by 

 chemical messengers (hormones) from the reproductive organs. 

 The splendid result is hardly finished before operations begin for 

 its being shed! And after all, the antlers do not seem to be of 

 much practical importance; they are exuberant outcrops of the 

 male's virile constitution. Perhaps they have their counterpart 

 in the male narwhal's spear. 



