SCLATER ON THE GENEEAL DISTRIBUTION OF AVES. 131 



which are most natural when their respective Faunae and Moras 

 are taken into consideration. The world is mapped out into so 

 many portions, according to latitude and longitude, and an attempt 

 is made to give the principal distinguishing characteristics of the 

 Fauna and Flora of each of these divisions ; but little or no at- 

 tention is given to the fact that two or more of these geographical 

 divisions may have much closer relations to each other than to any 

 third, and, due regard being paid to the general aspect of their 

 Zoology and Botany, only form one natural province or kingdom 

 (as it may perhaps be termed), equivalent in value to that third. 

 Thus in ' Johnston's Physical Atlas,' the earth is separated into 

 sixteen provinces for Ornithology, solely according to latitude and 

 longitude, and not after ascertainment of the amount of difference 

 of ornithic life in the respective divisions. Six of these provinces 

 are appropriated to America, one to Europe, and six to Asia, Au- 

 stralia, and the islands ; a very erroneous division, according to my 

 ideas, as I shall hereafter attempt to show. In Mr. Swainson's 

 article in Murray's ' Encyclopedia of Greography,' and in Agassiz's 

 introduction to Nott and Gliddon's ' Types of Mankind,' what I 

 consider to be a much more philosophical view of this subject is 

 taken. The latter author, in particular, attempts to show that the 

 principal divisions of the earth's surface, taking zoology for our 

 guide, correspond in number and extent with the areas occupied 

 by what Messrs. Nott and Gliddon consider to be the principal 

 varieties of mankind. The argument to be deduced from this 

 theory, if it could be satisfactorily established, would of course be 

 very adverse to the idea of the original unity of the human race, 

 which is still strongly supported by many Ethnologists in this 

 country. But I suppose few philosophical zoologists, who have 

 paid attention to the general law^s of the distribution of organic 

 life, would now-a-days deny that, as a general rule, every species 

 of animal must have been created within and over the geographic 

 area which it now occupies. Such being the case, if it can be 

 shown that the areas occupied by the primary varieties of mankind 

 correspond with the primary zoological provinces of the globe, it 

 would be an inevitable deduction, that these varieties of Man had 

 their origin in the different parts of the w orld where they are now 

 found, and the awkward necessity of supposing the introduction 

 of the red man into America by Behring's Straits, and of colonizing 

 Polynesia by stray pairs of Malays floating over the water like 

 cocoa-nuts, and all similar hypotheses, would be avoided. 



But the fact is, we require a far more extended knowledge 



