That an institution of the kind in question would tend to promote the solution of problems in 'evolutionary biology,' it seems needless to argue. Many of the most desirable experiments in heredity and variation, for example, require such prolonged time and such constant attention, that it is practically impossible for individual workers to undertake them; and, therefore, as M. Giard observes, they have never been undertaken. But if there were an _Institut transformiste_ to which material might be sent from any part of the world, with directions as to its treatment, biologists of all countries would be furnished with an opportunity of experimentally testing any ideas which might occur to them in regard to these or kindred matters. Again, it seems needless to remark that England ought to be regarded as the natural territory of an establishment of this character; that the establishment itself should be situated in the vicinity of others which are already devoted to the study of morphology and physiology; and that sufficient land should belong to the _Institut_ to admit of plots of ground being set apart for researches on plants, as well as buildings for the accommodation of animals. In order to satisfy all these conditions, the _Institut_ ought to be established either in Oxford or Cambridge; and at least, one skilled naturalist, one competent gardener, and one trustworthy keeper ought to be resident. This would involve an annual expenditure of between 300_l._ and 400_l._ But the capital sum which would have to be sunk in the purchase of land and the erection of buildings would not be considerable; because, in the first instance, at all events, two or three acres of ground would probably be sufficient; while the animal houses would be chiefly--if not exclusively--required for the accommodation of small mammalia, birds, insects, and aquatic organisms. Nevertheless, seeing that an initial expenditure of at least 1,000_l._ would be needed for the purposes just mentioned, as well as an annual income of at least 400_l._, and seeing that even this much money is not likely to be forthcoming for objects of a purely scientific nature, the scheme on behalf of which we solicit your opinion is the following. From inquiries which we have made here, we think it is probable that the University would take up the matter, or, at any rate, render important assistance thereto, if the Hebdomadal Council were satisfied as to the desirability of the project from a scientific point of view. It is on this account that we have ventured to address you upon the subject. The appended memorial is being sent, together with this circular letter, to all the other leading biologists in this country; and if you could see your way to signing the former, you would render additional weight to the body of authoritative opinion which it will eventually convey to the University.