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in the position of a hypothesis wanting proof, and objects strongly to its 
acceptance as an established theory, and especially to the consequences which 
have been drawn from it as such by the monistic philosophers of Germany ; 
consequences which, as we all know, tend completely to revolutionize all our 
ideas and practically amount to the establishment of a new religion and a 
new philosophy. His protest, in fact, which was called forth by discourses 
delivered on previous days by Professors Hackel and Nageli, and by Hr. 
Klebs, is, as he himself tells us, a “ protest against the attempts that are 
made to proclaim the problems of research as actual facts, the opinions of 
scientists as established science, and thereby to set in a false light, before the 
eyes of the less informed masses, not merely the methods of science, but also 
its whole position in regard to the intellectual li f e of men and nations.” 
Such a course, especially if the doctrine be expanded to the extent advocated 
by Professor Hackel and others, would, he holds, endanger that freedom of 
scientific opinion of which Professor Hackel’s own discourse furnished a most 
striking example ; and he considers that the teaching of such opinions in the 
schools as established truths, which was advocated by Professor Hackel, is 
very much to be deprecated. 
We must confess that we perfectly agree with Professor Virchow in his 
general argument, and more or less in the opinions which he expresses upon 
the subject of evolution, which he regards as still an open question, but un- 
doubtedly as possessing strong prima facie claims to acceptance. In these days 
we have got beyond the old scholastic reasoning, according to which a philo- 
sopher established his own theory by the mere fact of demolishing his 
opponent’s, and we can admit that a cause may have right on its side 
although its champion has weak places in his armour which he is not suffi- 
ciently skilful of fence to defend from the blows of his adversary. Professor 
Virchow endeavours rather to indicate some of these weak points than to 
invalidate the doctrine of evolution ; but at the same time he objects strongly, 
in the interests of science and not of theology, to the extreme dogmatism 
displayed by some of the most advanced evolutionists, who would have us 
believe that the origin, not only of organic forms but of the universe itself, 
has been fully explained. The translation appears to be remarkably well 
done. 
THE VERTEBRATES OF AMERICA.* 
W E have received from Professor Marsh a copy of a discourse on the 
Introduction and Succession of Vertebrate life in America, delivered 
by him before the American Association for the Advancement of Science, in 
August last. It is manifestly impossible within the compass of a single 
lecture to discuss in anything like detail a subject so vast, but Professor 
Marsh has succeeded in sketching out, in a most interesting fashion, the 
leading events in the history of the vertebrate type in America, where, as is 
well known, some sections, especially, of that sub-kingdom, are represented by 
an astonishing abundance and vaiiety of remains. Professor Marsh definitely 
accepts the theory of evolution, and endeavours, where possible, to indicate 
the probable lines of descent of the great groups of vertebrates. 
* “ Introduction and Succession of Vertebrate Life in America.” By 
Professor O. C. Marsh. 8vo., 1877. 
