...(Summary of Chap. V.) :— " Our ignorance of the laws of variation is profound. Not in one case out of a hundred can we pretend to assign, any reason why this...&c. seem to have induced some slight modifications. Hahit, in producing constitutional differences, and use, in strengthening, and disuse, in weakening...

...species, and the greater differences between species of the same genus. The external conditions of lite, as climate and food, &c., seem to have induced some...diminishing organs, seem to have been more potent in their effects. Homologous parts tend to vary in the same way, and homologous parts tend to cohere. Modifications...

...(Summary of Chap. V.) :— " Our ignorance of the laws of variation is profound. Not in one case out of a hundred can we pretend to assign any reason why this...the parents. .... The external conditions of life, aq climate and food, &c. seem to have induced some slight modifications). Habit, in producing constitutional...

...(Summary of Chap. V.) :— " Our ignorance of the laws of variation is profound. ITot in one case out of a hundred can we pretend to assign any reason why this...differences, and use, in strengthening, and disuse, ia weakening and diminishing organs, seem to have been more potent in their effects." And finally,...

...Nature as Mr. Darwin: — "Our ignorance of the laws of variation is profound. Not in one case out of a hundred can we pretend to assign any reason why this or that form has varied." "With respect to the exci ting causes we can only say as when speaking of so-called...

...Origin of Species): "Our ignorance of the law of variation is profound." " Not in one case out of a hundred can we pretend to assign any reason why this or that differs, more or less, from the same part in the parent." Again, he says (p. 157, Origin of Species):...

...nts. . . . The external conditions of life, :is climate anil foorl, etc., seem to have induced Home slight modifications. Habit, in producing constitutional...diminishing organs, seem to have been more potent in their effects." And finally, as if to prevent all possible miiconception, Mr. Darwin concludes his " Chapter...

...cannot tell. Finally, " our ignorance of the laws of variation is profound. Not in one case out of a hundred can we pretend to assign any reason why this or that part has varied." The conclusion of the whole matter is that "the one known cause of close similarity in...

...bundred can we pretend to assign any ienson why this or that pint varies more or less from the same pait in the parents. . . . The external conditions of life, as climate and food, etc., seem 1o have induced some slight modifications. Habit, in producing constitutional differences,...

...This is conceded: — "Our ignorance of the laws of variation is profound. Not in one case out of a hundred can we pretend to assign any reason why this or that form has varied." . . . " We are profoundly ignorant of the cause of each sudden and apparently spontaneous...