i6 Introductory 



Norway, and south in North-Western Africa. The elk and reindeer, although 

 impinging on the northern limit of the red deer group and in certain 

 districts overlapping it, are characteristic of a colder zone, where Rangifer is 

 practically circumpolar. On the other hand, the Oriental deer of the 

 rusine and rucervine groups are essentially inhabitants of hot countries, and 

 are abundant within the tropical zone. To a certain extent the sikas are 

 intermediate in this respect between the rusas and the red deer, occupying 

 to a large degree a zone between the two latter, but also intruding into the 

 area of each. Their occurrence in the European Pliocene suggests, however, 

 that comparatively warm regions formed their original habitat. The 

 American deer range between latitude 40 north and the extreme south of 

 the continent, and are accordingly able to stand excessive heat and a con- 

 siderable amount of cold. Among these, the brockets are mainly restricted 

 to hot climates, although one is found high up on the Cordillera ; while the 

 guemals are exclusively inhabitants of cold regions. The dorcelaphine 

 section would seem to have been originally a temperate form, as the southern 

 races allied to the Virginian deer are all small and apparently degraded 

 types. On the other hand, from the present distribution of the marsh-deer 

 and the number of allied extinct species in the Tertiary deposits of Northern 

 Argentina, the blastocerine group appears to prefer a hot climate. 



As already observed, remains of deer more or less closely allied to existing 

 types are met with throughout the formations of the Plistocene and Pliocene 

 epochs ; some of those from the former, such as Sedgwick's deer and the Irish 

 deer, attaining a development of antler unequalled by any living species. As 

 we descend in the Pliocene the antlers tend to become smaller and simpler; 

 and the distribution of the various groups is also found to differ considerably 

 from that obtaining at the present day. When we reach the Miocene, all 

 the deer are small, and their antlers never attain a development beyond that 

 of a simple fork ; while some of them were entirely devoid of these 

 appendages. In the Upper Oligocene of America there are a few forms 

 referred to the family in which the antlers, although simply forked, seem 

 to have been clothed with skin and were permanently retained; but the 

 Upper Oligocene deer of Europe were mostly devoid of antlers, and apparently 

 furnished with long upper tusks, or canines, while the lateral metacarpal 

 bones seem to have been complete. The earliest known form which can be 

 in any way affiliated to the deer tribe is a small ruminant from the Middle 



