380 CLASSIFICATION. Cnxr. XIII. 



All the modified descendants from A will have inherited some- 

 thing' in common from their common parent, as will all the de- 

 scendants from I ; so will it be with each subordinate branch of 

 descendants, at each successive stage. If, however, we suppose 

 any descendant of A or of I to have been so much modified as 

 to have lost all traces of its parentage, in this case, its place in 

 the natural system will likev>dse be lost — as seems to have oc- 

 curred with some few existing organisms. All the descendants 

 of the genus F, along its whole line of descent,' are supposed 

 to have been but little modified, and they form a single genus 

 But this genus, tliough much isolated, will stiil occupy its projv 

 er intermediate position. This natural arrangement is shown 

 in the diagram as far as is possible on paper, but in much too 

 simple a manner. If a branching diagram had not been used, 

 and only the names of the groups had been written in a linear 

 series, it would have been still less possible to have given a 

 natural arrangement ; and it is notoriously not possible to rep- 

 resent in a series, on a flat surface, tlic aflinities which we dis- 

 cover in Nature among the beings of the same group. Thus, 

 on the view which I hold, the natural system is genealogical 

 in its arrangement, like a i^edigrcc ; but the amount of modifi- 

 cation which the different groups have undergone has to be 

 expressed by ranking them und(?r different so-called genera, 

 sub-families, families, sections, orders, and classes. 



It may be worth while to illustrate this view of classification, 

 by taking the case of languages. If we possessed a perfect 

 jiedigree of mankind, a genealogical arrangement of the races 

 of man would afford the best classification of the various lan- 

 guages now spoken throughout the world ; and if all extinct lan- 

 guages, and all intermediate and slowly-changing dialects, had 

 to be included, such an arrangement would be the only pos- 

 sible one. Yet it might be that some ancient languages had 

 altered very little and had given rise to few new languages, 

 while others had altered much, o\\'ing to the spreading, isola- 

 tion, and state of civilization of the several co-descended races, 

 and liad thus given rise to many new dialects and languages. 

 The various degrees of difference between the languages of 

 tlie same stock would have to be expressed by groups subordi- 

 nate to groups ; but the proper or even only possible arrange- 

 ment would still be genealogical ; and this would be strictly 

 natimal, as it would connect together all languages, extinct and 

 recent, by the closest affmitics, and would give the filiation and 

 origin of each tongue. 



