ZOOLOGICAL POSITION AND STRUCTURE 25 
reduction of the fibula has been carried to a still 
greater degree, only the upper portion remaining as 
a small pointed rod of bone welded to the outer side 
of the upper end of the tibia — yet another example 
of parallelism between ruminants and the horse tribe. 
None of the foregoing skeletal features is, of course, 
observable in the living animal, but there is one very 
distinctive external character common to at least the 
males of all existing species of the typical ruminants 
in a wild state, with the exception of certain small 
kinds of deer, such as the musk-deer and water-deer 
of Asia. This is the presence on the upper part of 
the head of paired appendages, known in the case 
of deer as antlers, and in that of the members of 
the bovine family as horns, the nature of these 
appendages serving to divide the typical ruminants 
into three or four distinct families. 
In the case of the deer family, or Cei'vidcE^ in 
which, with one exception, they are restricted to the 
males, these appendages take the form of outgrowths 
of bare bone, occasionally as mere spikes, but generally 
divided up into a smaller or greater number of 
branches. These antlers, as they are best called, in 
order to distinguish them from the horns of the ox 
and its relatives, grow from permanent, skin-covered 
prominences, or pedicles, arising from the frontal 
bones of the skull, and are themselves at first covered 
with a velvety skin, which subsequently dries up and 
is rubbed off. These antlers are shed and renewed 
every year, or at least every few years ; and their 
presence, coupled with certain structural features which 
need not now be mentioned common to the species 
unprovided with these appendages, serves to differen- 
tiate the Cervidce from the bovine ruminants. 
