Page:JehuTJ 1902redux(1).pdf/27

26

organisms". It is difficult to see for instance, how the extraordinarily co-ordinated actions displayed by a frog after its cerebrum is removed and wnen it is forced to balance itself on a moving surface, can be explained unless the Lamarckian factors have had something to do with their origin. Darwin and after him Romanes called in the principle of what was termed by G.H. Lewis "lapsing intelligence" in order to account for some instincts. Romance distinguished instincts which arose in this way as "secondary"; reserving the term "primary" for those whose origin can be fully explained by natural selection. It is generally admitted that natural selection is inadequate to account for all instincts and in order to get over the difficulty the principle of "organic selection" has been called in. But this has one great drawback - it requires an enormous range of time. Though the inheritance of acquired characters has not yet been proved, it cannot be said to have been disproved. Perhaps that
it is impossible but it is important to note that there are phenomena for which no satisfactory and full explanation can be found unless the Lamarckian factors are allowed to have had a share in the process of organic evolution
isolation.