Chap. XIV.] CLASSIFICATION. 215 



groups; but the proper or even the only possible ar- 

 rangement would stiU be genealogical; and this would 

 be strictly natural, as it would connect together all lan- 

 guages, extinct and recent, by the closest affinities, and 

 would give the filiation and origin of each tongue. 



In confirmation of this view, let us glance at the 

 classification of varieties, which are known or believed 

 to be descended from a single species. These are 

 grouped imder the species, with the sub-varieties under 

 the varieties; and in some cases, as with the domestic 

 pigeon, with several other grades of difference. Nearly 

 the same rules are followed as in classifying species. 

 Authors have insisted on the necessity of arranging 

 varieties on a natural instead of an artificial system; we 

 are cautioned, for instance, not to class two varieties of 

 the pine-apple together, merely because their fruit, 

 though the most important part, happens to be nearly 

 identical; no one puts the Swedish and common turnip 

 together, though the esculent and thickened stems are 

 so similar. Whatever part is found to be most con- 

 stant, is used in classing varieties: thus the great agri- 

 culturist Marshall says the horns are very useful for 

 this purpose with cattle, because they are less variable 

 than the shape or colour of the body, &c.; whereas with 

 sheep the horns are much less serviceable, because less 

 constant. In classing varieties, I apprehend that if we 

 had a real pedigree, a genealogical classification would 

 be universally preferred; and it has been attempted in 

 some cases. For we might feel sure, whether there had 

 been more or less modification, that the principle of 

 inheritance would keep the forms together which were 

 allied in the greatest number of points. In tumbler 

 pigeons, though some of the sub-varieties differ in the 



