i8yi.] Notices of Books. 249 



attempt to trace this descent in one or more lines ? In other 

 words, are all the various races of mankind to be included in one 

 species or in several? It must be borne in mind that this question 

 is not the same as whether mankind are sprung from one original 

 pair. When the evolutionist supposes that one species of 

 animal or plant has been evolved out of a pre-existing closely- 

 allied form, it is not necessary to assume that all the existing 

 individuals are descended from some one aberrant off-shoot of the 

 original stock ; the whole race may have gradually changed by 

 the operation ofthelawofthe Survival of the Fittest, owing to some 

 alteration in its external environment, so that it may be im- 

 possible to draw a line of demarcation between the earlier and 

 the later form. This is doubtless the manner in which all 

 evolutionists must hold that man gradually arose by continuous 

 modifications from his nearest structural relatives, the anthropoid 

 apes ; but whether in one or several lines of descent is an open 

 question. Mr. Wallace, in his essay on " The Development of 

 Human Races under the Law of Natural Selection," while 

 stating the arguments on both sides of the question, sums up on 

 the whole in favour of the primitive diversity of man ; Mr. 

 Darwin we understand to hold a different opinion. We could 

 have wished that his views on this point had been more explicitly 

 stated ; we draw our conclusion rather from his mode of ex- 

 pressing himself than from any definite statement, and from the 

 absence of any allusion to more than one such line of descent. Let 

 us examine his arguments a little more in detail. 



Starting with the main principle of the theory of Natural 

 Selection, that all organic species tend spontaneously to vary from 

 the parent form, generally to a very small extent, and that those 

 variations only survive and become hereditarily perpetuated 

 which present some advantageous point of structure in com- 

 parison with their fellows, Mr. Darwin applies this principle to 

 the case of man, stating that, "in order that an ape-like creature 

 should have been transformed into man, it is necessary that this 

 early form, as well as many successive links, should all have 

 varied in mind and body. It is impossible to obtain direct 

 evidence on this head ; but if it can be shown that man now 

 varies — that his variations are induced by the same general 

 causes, and obey the same general laws, as in the case of the 

 lower animals — there can be little doubt that the preceding in- 

 termediate links varied in a like manner. The variations at each 

 successive stage of descent, must, also, have been in some manner 

 accumulated and fixed." One of the earliest changes must have 

 been in the shape of the hands and feet. The hands and feet 

 of the anthropoid apes are admirably adapted for climbing trees 

 and obtaining their food. Baboons, however, which frequent 

 hilly and rocky districts, and only from necessity climb up high 

 trees, habitually use their feet for walking along the ground, and 

 have acquired almost the gait of a dog. In order to enable man 

 to obtain mastery over those arts which have raised him so 



VOL. VIII. (O.S.) — VOL. I. (N.S,) K 2 



