[101]

Ch 4

I found in Ch. 7 that I must already have explained, why & how I suppose that sub-genera are usually of more recent origin than genera — The sub-vars of Carrier presuppose existence of Carrier —of fantail of fantail Carrier & Fantail of Dovecot — they may have branched off at very different periods — in nature extinction will generally kill old forms.— Dovecot surely might have have been altered in one unbroken line into

[101v]

Carrier; but this does not seem to be course of nature — that one part breaks into many forms owing to advantages which it has.—

Does the existence of sub-varieties presuppose an already existing variety, why may not a species give off a succession of sub-varieties — No they wd be a lot of close varieties.— If then sub-vars implies they have much in common & differing from other varieties.