HORNS AS A SEXUAL CHARACTER 201 



same os cornu, which may however be branched, but which is in 

 the same way covered by a layer of modified integument ; this is 

 known as the " velvet " ; it only lasts for a certain period, and is 

 then torn off by the exertions of the animal itself, leaving behind 

 the bony core, which is popularly termed the horn. It will be clear 

 that here is only a difference of comparative unimportance ; the 

 same essential featm-es are present in both groups of animals, but 

 the modification of the epidermis has progressed along different 

 lines. Both can be referred back to the primitive conditions seen 

 in the paired horns of the Giraffe. Even the difference, such as it 

 is, is bridged over by the Antelope Antilocapra, where the os cornu 

 is bifid and the horn is periodically shed, as is the velvet of the 

 stag ; but in the stag the bony part of the horn is also shed, a 

 state of affairs which has ho parallel in the Hollow-horned 

 Kuminants. The great Sivathernim may conceivably be an 

 annectant form between the two types of compound horns, i.e. 

 those of the Antelope and those of the Deer. This creature had 

 two pairs of horns, of which, naturally, only the bony cores remain ; 

 the hinder pair of these were branched. But although so far they 

 resemble the Deer's horns rather than the Antelope's, Dr. Murie 

 has thought that they were covered by a horny sheath and not by 

 soft skin as in the Deer. In any case these horns were apparently 

 never shed, which is a point of likeness with the Antelope and of 

 difference from the Deer. Apart thel-efore from the nature of the 

 covering of the bony cores, there are good grounds for looking 

 upon them as intermediate between those of the Deer and those 

 of the Antelopes. 



The horns of the Ruminants are frequently a secondary sexual 

 character ; this is especially the case with tlie Deer. The Rein- 

 deer is, however, an exception, both the stags and the does 

 having horns. That they are associated with the reproductive 

 function is shown by their being shed after the period of rut, 

 the destruction of the velvet at that period, and also by the effect 

 upon the horns wiiich any injury to the reproductive glands 

 produces. Some useful facts upon this latter head have been 

 amassed by Dr. G. H. Towler,^ who noticed in a series of stags, 

 horns showing various degrees of degeneration in the antlers pro- 

 duced by varying degrees and periods of gelding. From the facts 



^ "Notes on some Specimens of Antlers of the Fallow Deer, etc.," I'roc. Zool. Soc. 

 189-1, |). 48.0. 



