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performance of proper experiments will alone lead to their solution. A new school of experimental evolutionists has arisen whose avowed object is to eschew speculation and to find out what actually does occur in nature. It is important to find what part acquired characters play in the origin of species. Acquired characters form a large proportion of the characters of adults. How large it is not easy to determine. It is often too readily concluded that characters which appear constantly in successive generations are congenital; many of them are doubtless acquired afresh by each generation owing to the fact that the external conditions remain constant. It has not yet become possible to separate with certainty those characters which are genetic from those which are acquired. Though much has been done already, more experimental evidence is still needed with a view of finding what characters depend upon the environment. Plants and animals require to be placed under new conditions and the results noted. And with rapidly breeding forms the observations can be continued for many generations. In carrying out such experiments it is of great importance to note not only the changes which occur in the organism when brought under new conditions but also, and this is too often forgotten, to find what happens to such organisms when transported back to the old conditions. This would throw light on the question of the transmissibility of acquired character. Botanists, as a result of their
se experiments and observations are fairly unanimous