DECIDUOUS NATURE OF^DEER ANTLERS 349 



it may seem astonishing that births occur every month, and hence 

 copulation as well, although the bucks have rubbed-off antlers only 

 for a comparatively brief period of the year, and the last of them 

 shed theirs only when the first begin to rub the velvet ofi^ in June. 

 As hog deer live in pairs, and the distribution of the sexes is approxi- 

 mately equal, the buck dees not have to do much battling to possess 

 its female. Its antlers are not as necessary to it as a weapon as in the 

 larger species, and it willingly and fertilely copulates even when in 

 velvet. The same is true of Axis ( and Melanaxis ) , where the females 

 are likewise regularlv in rut." The validity of this interesting aspect 

 of the problem has been verified by histological examination of testes 

 from 4 Venezuelan deer {Odocoileus gymnotis) generously made 

 available to the author by Dr. Pedro Trebbau, Director of the Jardin 

 Zoologico in Caracas. Mature sperm were present in abundance 

 regardless of whether or not the velvet had been shed from the 

 antlers, a condition which contrasts markedly with the seasonal 

 variations in spermatogenesis that were observed by Wislocki 

 (1949) in Odocoileus virginianus inhabiting temperate North 

 America. 



The data presented by Cabrera and Yepes (1940) indicate that 

 in South America the seasons of shedding are increasingly irregular 

 in proportion to the proximity of habitat to the equator. The hue- 

 mul, Hippocamehis bisulcus, which inhabits the Andes Mountains 

 of Argentina and Chile, sheds its antlers in the winter and grows 

 new ones in the spring. ( Gigoux ( 1929 ) , however, claims that 

 antlers are shed in December (i.e. late spring) in this species.) The 

 pampas deer (Ozotocerus bezoarticus) , which lives between 5° 

 and 41° south latitude, sheds its antlers at variable times but most 

 frequently in May (i.e. late autumn). The swamp deer {Blastocerus 

 dichotomns) inhabiting southern Brazil and adjacent countries does 

 not shed at any fixed season. Mazama rufa, the red brocket, inhabits 

 the near-equatorial regions of Brazil, Venezuela, Colombia, and the 

 Guianas. Accordingly, it sheds its antlers at any time of year. In 

 Venezuela, data gathered bv the author on Odocoileus gymnotis 

 indicate that antler cycles are probably asynchronous among the 

 members of local populations. Comparable infonnation regarding 

 other South American species (e.g., Hippocamelus antisensis and 



