138 Thomas Henry Huxley 



a scientific basis, practicall}^ for the first time, by a 

 memoir on the geographical distribution of birds pub- 

 lished in ihe /ounia/ of the Linnaean vSociety of London. 

 It was known in a general way that different kinds of 

 creatures were found in different parts of the world, 

 but little attempt had been made to map out the world 

 into regions characterised by their animal and vege- 

 table inhabitants, as the political divisions of the world 

 are characterised by their different governments and 

 policies. Mr. Sclater, who two years later became sec- 

 retary of the Zoological Society of London, in his 

 memoir introduced the subject in the following words : 



" It is a -well-known and universally acknowledged fact that 

 we can choose two portions of the globe of which the respective 

 fauna and flora shall be so difierent that we should not be far 

 wrong in supposing them to have been the result of distinct 

 creations. Assuming, then, that there are, or may be, more 

 areas of creation than one, the question naturally arises how 

 many of them are there, and what are their respective extents 

 and boundaries ; or, in other words, what are the most natural 

 primary outological divisions of the earth's surface ? " 



Mr. Sclater' s answer was that there are six great 

 regions; Neotropical, Nearctic, Palsearctic, Ethiopian, 

 Indian, and Australian, and his answer, with minor 

 alterations and the addition of a great wealth of de- 

 tail, has been accepted by zoology. 



Two years later, however, Darwin gave a new mean- 

 ing and a new importance to Sclater' s work, by the 

 new interpretation he caused to be placed on the words 

 " centres of creation." Sclater's facts and areas re- 

 mained the same ; Darwin rejected the idea of separate 

 creations in the older sense of the words, and laid stress 

 on the impossibility of accounting for the resemblances 

 within a region and for the differences between regions 



