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Show pART I.-THE DESCENT OF MAN. CHAPTER I. THE EVIDE~CE OF TilE DESCENT OF MAN FROM SOlliE . LowER FonM. N"ature of the evidence bearing on the origin of man- Homologous structures in man and the lower animals- Miscellaneous points of correspondence - Development - Rudimentary structures, muscles, sense-organs, hair, bones, reproductive organs, &c.The bearing of these three great classes of facls on the origin of man. HE who wishes to decide whether man is the modified descendant of some pre-existing form, would probably £rst enquire whether man varies, however slightly, in bodily structure and in mental faculties; and if so, whether the variations are transmitted to his offspring in accordance with the laws which prevail with the lower animals; such as that of the transmission of characters to the same age or sex. A gain, are the variations there. sult, as far as our ignorance permits us to judge, of the .same general causes, and are they governed by the same generalla\vs, as in the case of other organisms; for instance by correlation, the inherited efiec.ts of use and -disuse, &c.? Is man subject to similar malconformations, the result of arrested development, of reduplication of parts, &c., and does he display in any of his anomalies reversion to some former and ancient type of structure? It might also naturally be enquired whether man, like so many other animals, has given rise to varieties and sub-races, differing but slightly from each other, or to |