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scarcely any reasonable way of avoiding the admission that real variation occasionally occurs, looks looks upon variation in a way very different from that in which it was regarded by Darwin. He assures us that

variation from step to step in the series must occur either by the addition or by the loss of factors. Now, of the origin of new forms by loss there seems to me to be fairly clear evidence, but of the contemporary acquisition of any new factor I see no satisfactory proof, though I admit there are rare examples which may be so interpreted. We are left with a picture of variation utterly different from that which we saw at first. Variation now stands out as a definite physiological event. We have done with the notion that Darwin came latterly to favor, that large differences can arise by accumulation of small differences. Such small differences are often mere ephemeral effects of conditions of life, and as such are not transmissible; but even small differences, when truly genetic, are factorial like the larger ones, and there is not the slightest reason for supposing that they are capable of summation.

The hypothesis that variation is due to the loss of something in the germ plasm is carried out to its logical conclusion. In speaking of the colors of sweet peas he says,

There is no question that these have been derived from the one wild bicolor form by a process of successive removals. When the vast range of form, size, and flavor to be found among the cultivated apples is considered, it seems difficult to suppose that all this variety is hidden in the wild crabapple. I cannot positively assert that this is so, but I think all familiar with Mendelian analysis would agree with me that it is probable, and that the wild crab contains presumably inhibiting elements which the cultivated kinds have lost.

Thus progressive variation and even dominant characters represent no real additions to the germinal complex; they are due simply to the removal of inhibitory factors. "I have confidence," Bateson continues, "that the artistic gifts of mankind will prove to be due not to something added to the make-up of an ordinary man, but to the absence of factors which in the normal person inhibit the development of these gifts. They are almost

beyond doubt to be looked upon as releases of powers normally suppressed. The instrument is there, but it is 'stopped down.'"

Great intellectual genius might be considered as mediocrity minus a factor for the inhibition of intellect; and to carry the theory out consistently, the ordinary man may be conceived to owe his intellectual status to the removal of a factor for feeble-mindedness which may have suppressed the latent abilities of his pre-cave ancestors. What possibilities for future development may lie before us if only the process of subtraction be carried sufficiently far!

The point of view developed by Professor Bateson, which some were inclined to believe he did not wish to be taken quite seriously, was soon afterward taken up by Dr. C. B. Davenport, director of the Station for Experimental Evolution at Cold Spring Harbor, and head of the Eugenics Record Office, who put forward, apparently in all earnestness, the view that our remote protozoan ancestors were much more complex in their chemical composition than the germ plasm of the higher evolved types of today, which owe their rise to the successive losses of inhibitory chemicals.

Such pronouncements from leading investigators of Mendelian heredity, reminding one as they do of the extravagances of the preformation theories of Leibnitz, Haller, and Bonnet in the seventeenth and eighteenth centuries, naturally somewhat startled the public, as they were doubtless intended to do. Professor Bateson, who for many years had been somewhat restive under the rather unsatisfactory state of evolutionary speculation, finding in the recently opened field of Mendelian inheritance opportunities more congenial to his powers than the laborious compilation of meristic and substantive variations, had thrown himself into the work of Mendelian analysis with signal success. In his position as leader of the English Mendelians he doubtless derived a

peculiar satisfaction in wielding his iconoclastic club. No one can really understand the address before the British Association which has perplexed so many people, without reading much between the lines, and without making an allowance for the effect of certain instinctive proclivities of human nature, which are not without considerable influence in shaping the standpoint even of highly trained scientific men. Bateson committed, I believe, the very human error of attributing to recent discoveries in Mendelian inheritance, in which he had taken so prominent a part, an importance for evolutionary theory far beyond what they really possessed. There is nothing in Mendelian inheritance that gives the slightest indication of what is the nature of those factorial changes upon which the appearance of so-called unit characters depends. That even recessive characters are due to loss is a perfectly unwarrantable assumption, and that dominant characters arise as a result of losses in the germ plasm is a conclusion for which there is not a shred of real evidence. It is somewhat remarkable that Professor Bateson should have presented addition and subtraction as the alternative methods of factorial changes, and that he should have failed even to mention the possibility of factorial modification or transformation, which would seem a priori to be a very probable occurrence. The dilemma in which he represents evolutionary theory as being placed through recent discoveries in heredity and variation is one which is entirely fanciful and depends upon reading into nature a purely artificial and symbolic interpretation.

The discoveries in the few years that have elapsed since the publication of Bateson's address have not only failed to strengthen the paradoxical position there set forth, but have afforded positive evidence of its unsoundness. In the first place, the discovery of what Morgan calls multiple allelomorphs has created serious difficulties for the "presence-absence theory" upon which Bateson relies and has lent strong support to the view

that Mendelian characters are due to factor transformation instead of merely gains or losses. Recent work has afforded further and critically tested evidence of the origin de novo of dominant characteristics. It has shown that recessive genes occasionally mutate to form dominant factors. In fact there may be a whole series of changes in what the evidence indicates is a single gene. Recent work has also furnished additional evidence of the effectiveness of selection in gradually accumulating differences as well as in revealing more clearly the precise method by which such results are brought about. We are by no means "done with the notion . . that large differences can arise by accumulation of small differences." In fact, it has been repeatedly demonstrated that relatively large differences have been formed by this very method. It is becoming clearer that species in a state of nature differ by a multitude of factors for relatively small differences, and that, since there is not the slightest observable tendency toward simultaneous mutation in different genes, these species must have arisen by a succession of small steps. The mutation theory of de Vries has had to be seriously modified, and has been brought more nearly in accord with the conception of the origin of species by the gradual method as outlined by Darwin.

When we look back upon the progress that has been made in genetics during the past twenty years, we can scarcely fail to recognize the period as one of substantial achievement. The method of evolution has come to be less a matter of philosophical speculation and more a subject for attack by the methods of experimental inquiry. The present is a period in which fruitful researches are being vigorously prosecuted along a number of lines. bearing on the central problem. We may or may not be near the dawn of any great and epoch-making discoveries. But a steady advance is going on over a wide front, which no doubt will lead to the ultimate conquest of positions of capital importance.

THE GOVERNMENT OF UNIVERSITIES

W. A. MERRILL

The American university has had a disorderly and fortuitous development from the germ of the English college. Harvard College was modeled after Emmanuel College in Cambridge, which was governed by a president and fellows, and Yale followed the precedent of Harvard. In the English system the university was the degree giving body and represented the general interests of the academic community with reference to the Crown and the public. The college housed and fed its students spiritually, materially, and intellectually, and prepared them for the university tests for degrees. Thus the college and not the university was the alma mater. The university controlled the student whenever he was beyond the college gates. Each college managed its own. affairs, usually in accordance with a charter granted by the Crown, and was subject to official visitation when there was ground for suspecting violation of charter provisions. The head of the college had various namespresident, warden, provost, master, rector; and American colleges have used one or the other of these titles for the designation of their principal officer. The corporation of the college included the fellows who conducted the business of the foundation, and who might or might not do the teaching; and there were students supported by the endowments, and these were known as scholars, postmasters, demis, and by other strange titles. The direct responsibility for the instruction was given to tutors and lecturers, who were usually fellows.

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