22 Introductory 



Distribution. — In the study of any group of animals their distribution 

 over the surface of the globe forms nowadays one of the most important 

 factors. And distribution may be divided into two sections, namely, the 

 present or geographical distribution, and the past or geological distribution. 

 As regards the former of these, a few words are necessary to explain the 

 divisions into which the world may be parcelled out from the distribution 

 of mammals. First, there are three primary divisions respectively 

 named the Notogauc, Neoganc, and Arctoganc realms. The first of these, 

 with which we have but little concern in this volume, includes New 

 Zealand, Australia, New Guinea, New Ireland, New Caledonia, etc. The 

 second contains the Neotropical region, which embraces the southern 

 portion of Mexico, Central and South America, and the West Indies. 

 The third, and by far the largest realm, consists of the rest of the world, 

 and is divided into several regions. These include the Malagasy region, as 

 represented by Madagascar and the Comoro Islands ; the Ethiopian region, 

 embracing Africa south of the Sahara ; the Oriental region, containing 

 India, Southern China, and the Malayan countries, the islands of Celebes 

 and Timor, being, on the whole, best placed here, although their faunas 

 show some affinities with that of Australia; the Holarctic region, embrac- 

 ing the greater part of Asia, Europe, North America, and Africa north of 

 the Sahara ; and the Sonoran region, which contains all the southern parts 

 of North America not included in the Neotropical. The great Holarctic 

 region may be divided into an eastern and a western division, the former 

 embracing all the Old World countries constituting the region, and the 

 latter such part of North America as comes within its limits. From the 

 eastern division of the Holarctic some writers cut off Northern Africa and 

 the other Mediterranean countries, together with those forming the 

 northern boundary of the Oriental region, to constitute a separate Mediter- 

 ranean region. 



A.S regards the geographical distribution of the deer tribe, the most re- 

 markable fact is their entire absence from the whole of the Ethiopian region. 

 By far the greater number of generic and sub-generic types are confined 

 to the Old World, which is likewise the habitat of the majority of the 

 species. The occurrence of deer without antlers, and also of forms allied 

 to the muntjacs in the Oligocene and Miocene Tertiary strata of Europe, and 

 likewise of others possessing antlers of the sikine and perhaps the rusine 



