tion are great variability, large numbers of 



individuals. the pnmpW ' 



orossing, isola.fr'pp in confined areas (yet 

 probably still more Qn gflt.F Tlg1 ' nn -- rvTOr nrm - 

 especially if oscillating in 



level), and considerable lapse of thrift- But 

 the lapse of time by itself must not be sup- 

 posed to do anything (as if the forms of life 

 were undergoing change by some innate 

 law), but merely to afford increased oppor- 

 tunity for variation and environmental 

 change, 



.arr on thr Tvnyj \^ thp lafit word 9! 



The divergence of character brought about 

 by artificial selection in domestic breeds is 

 efficiently paralleled in Nature, since the 

 more. diy^rsifieH the offspring of each species. 



the economy of Nature, and so increase in 



HlHTlb Agg rli^ rP^tp^f g.-mnnnt. nf hfg pan 



be supported by iucreasei] 



each species being; a.Ha.pt.eH....t ( p a. 



^ft L fjff p^^^^nc Tin's rlK^rg^nn^ 



of character, with extinction of intermediate 

 forms, explains the difficulties of classification 

 of making a genealogical tree which will 

 express the facts of the^ase and represent 

 diagrammatically "the great tree of life, 

 which fills with its dead and broken branches 



