Lyd 
SOME EXTINCT ARGENTINE MAMMALS 
In the preceding article I brought under the notice of the 
reader some of the leading peculiarities of the living and 
extinct faunas of South America in general and of Argentina 
in particular, while something was said as to the geological 
features of the latter country. I now propose to take into 
consideration the leading features of a few of the more 
remarkable types of certain groups. As most of these animals 
are known solely by their bones, it is, of course, impossible 
to avoid the introduction of a certain amount of anatomical 
details, although I have endeavoured to put these in as 
popular a manner as possible. 
As mentioned in the last article, among all the fossil 
animals of Argentina some of the most remarkable are the 
extinct ungulates, or hoofed mammals, which, exclusive of 
the horses, deer, guanacos, and mastodons, belong to groups 
almost unknown in any other part of the world.* Before 
going further, I must, however, remind my readers that 
existing ungulates are divided into four groups or sub- 
orders, distinguished from one another by the structure 
of their feet. Of these the elephants, or proboscideans, are 
specially characterised by having five toes to each foot, 
and by the two rows of bones in the wrist and ankle 
being arranged one above another in a linear manner ; 
* During the Pleistocene period a few ground-sloths and glyptodons 
entered North America. 
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