1 4 IXTllODUCTIOX. 



Sub-kingdom, Vertebrata. 



Class, Mammalia. 



Order, Carnivora. 



ramily, Ci.i n idw. 



(ieiius, Canis. 



Species, Canis faiailiaris. 

 In an ordinary way, however, it is quite unnecessary to employ in 

 practice any of the above names except the last or specific name, 

 since that implies all the others. 



The remainder of this work will be occupied with the considera- 

 tion of the chief characters of the more important groups into which 

 the animal kingdom has been divided, omitting those which are not 

 of paramount intei'est ; but it will be necessary fii'st to say a few 

 words as to the distiibution of animals in space and in time. 



5. Distribution of Anim.vls in Space and in Time. 



Distribution in Space. — The distribution of animals in space, or 

 their geographind distribution, is a department of zoology which is 

 concerned with determining the limits within which each species of 

 animal is at the present day confined. Save man, and his faithful 

 attendant the dog, no species of animal can be said to have anything 

 like a mdversal distiibution ; and each species, as is a matter of com- 

 mon observation, belongs to a certain region, and is confined within 

 wider or narrower limits. Thus the Giraffe, for exainjile, is not known 

 to exist out of Africa ; the Kangaroos belong to Australia ; the Arma- 

 dillos do not occur out of South America, — and so on. Further than 

 this, it is possible to divide the earth's surface into a certain number 

 of geographical regions or ^^ zou'irfical prorinres," each of which is 

 characterised by the occurrence in it of certain associated forms of 

 animal life. Under the head, therefore, of " distribution in space," 

 come two differenj but allied branches of imjuirv. Firstly, we have 

 to inquire as to the geographical range enjoyed l>y each individual 

 species of animal ; and secondly, we have to determine what general 

 assemblages of animals characterise certain large areas or provinces, 

 and this alone demands a biief consideration here. 



The geographical distribution of land animals is conditionea partly 

 by the existence of siutable surroundings, and jiartly by the presence 

 of barriers preventing migrations. Thus, certain contiguous regions 

 might be equally suitable for the existence of the same animals, but 

 they might belong to different zoological provinces if se|iarated by 

 any impassable barrier, such as a lofty chain of mountains. Owing 

 to their power of flight, the geographical distribution of birds is much 

 lejii limited than that of Mammals ; and many migratory birds may 



