The Zoology of North American Big Game 



the tarsal gland as well. The last three sub-genera 

 are South American and do not enter the United 

 States. Another genus, Pudua, from Chili, is 

 much like the brockets, but has exceedingly short 

 cannon bones, and some of the tarsal bones are 

 united in a manner unlike other deer. In all, thirty 

 specific and sub-specific names are now carried on 

 the roll of Mazama and its allies. 



Attention has already been directed to the paral- 

 lelism between the course of progress from simple 

 to complex antlers in the development of the deer 

 tribe, and the like progress in the growth of each 

 individual, and to the further fact that all the 

 stages are represented in the mature antlers of ex- 

 isting species. But a curious result follows from 

 a study of the past distribution of deer in America. 

 At a time when the branched stage had been 

 already reached in North America, the isthmus of 

 Panama was under water; deer were then absent 

 from South America and the earliest forms found 

 fossil there had antlers of the type of M. vir- 

 giniana. The small species with simple antlers only 

 made their appearance in later periods, and it fol- 

 lows that they are descended from those of com- 

 plex type. This third parallel series, therefore, in- 

 stead of being direct as are the other two, is re- 

 versed, and the degeneration of the antler, which 



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