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up of a continuous land, it is difficult to pronounce: 

 nevertheless, it is most consistent with both reason 

 and analogy to suppose that each of those causes has 

 operated to induce a similar result; and that we must 

 therefore view them as working in concert, if we would 

 appreciate their action aright. 



It is a law to which a large proportion of the organic 

 creation would appear to be subject, that the exuberance 

 of life (not so much, however, as regards the number of 

 individuals which the various species may present, as in 

 the grandeur of their size) has reference to the magni- 

 tude of the spot over which it is permitted to range. 

 The unnatural breeding-in of a single race, which must 

 of necessity happen unless the intercourse with other 

 varieties of its kind be possible, has always been attended 

 with effects more or less pernicious ; and in the Annu- 

 lose tribes I believe that the reduction of space which 

 geological convulsions have at various epochs brought 

 about, has been commonly succeeded (inter alia) by a 

 reduction of stature in those species which have been 

 cut off from their fellows. I do not assert that there are 

 no exceptions to this rule; for counter-influences may 

 at times prevail (as we shall shortly see), to neutralize 

 the above tendency. I hold it, however, as an absolute 

 truism, in physics, that a law without an exception is 

 an anomaly. If, therefore, we were once to admit the 

 latter to negative the former, no such thing as a law 

 could exist. Hence it follows, as a corollary (unless, 

 indeed, we are prepared to endorse that conclusion), that 



