76 SEXUAL DIMORPHISM 



We must, however, consider the possible course of the 

 evolution more particularly, for when we examine the subject 

 in detail we find many difficulties. The mechanical straining 

 of the antlers in a living stag takes place after the velvet is 

 shed, and when the antler is fully developed, so that it pro- 

 duces no growth of the antler, is on the contrary followed by 

 the shedding of the appendage, while the growth of the new 

 antler takes place without any mechanical irritation, before 

 the rutting season, and therefore the fighting, has commenced. 

 My hypothesis assumes that originally the fighting took place 

 while the antler was covered with skin, and capable of growth, 

 so that the growth followed the irritation, not preceded it. 

 Further, the explanation offered above does not give sufficient 

 reasons for the regular shedding of the antler by separa- 

 tion below the burr as a definite natural process, not an 

 accidental removal. 



We will consider, therefore, what is known concerning the 

 historical evolution of the typical antler, and see if it enables 

 us to remove these difficulties. Some of the extinct deer, and 

 doubtless the primitive ancestors of all antlered deer, were 

 entirely destitute of antlers, and there are certain existing 

 deer which do not possess these appendages. The latter are 

 ITi/drelaphus, the Water-deer of China, and Moschus, the 

 Musk-deer. The last is somewhat aberrant, but the former 

 is a true deer, and probably has never developed antlers 

 because it fights with its canine teeth, which in the male are 

 long, and grow from persistent pulps. 



We seem to get evidence of the actual origin of the antlers 

 in the extinct genus Dremotherium, the bones of which have 

 been obtained from the Miocene beds of France, Bavaria, etc. 

 According to Mr. Lydekker l these are probably the actual 

 ancestors of the modern deer of the Old World. The earlier 

 forms are all without antlers, while those from the Miocene 



1 Deer of All Lands, Rowland Ward, 1898. 



