ut CRITICISMS ON “ THE ORIGIN OF SPECIES” 81 
Reader, for February 27th of this year) supporting 
ilar views with all the weight of his special 
snowledge and established authority as a linguist. 
Professor Haeckel, to whom Schleicher addresses 
himself, previously took occasion, in his splendid 
monograph on the Radiolaria,' to express his high 
appreciation of, and general concordance with, Mr. 
Jarwin’s views. 
But the most elaborate criticisms of the “ Origin 
of Species” which have appeared are two works of 
very widely different merit, the one by Professor 
\K6lliker, the well-known anatomist and _histolo- 
gi st of Wiirzburg; the other by M. Flourens, 
Perpetual Secretary of the French Academy of 
)Sciences. 
Professor Kolliker's critical essay ‘“ Upon_the 
‘Darwinian T eory” is, like all that proceeds from 
‘the pen of that thoughtful and accomplished 
writer, worthy of the most careful consideration. 
\It comprises a brief but clear sketch of Darwin’s 
views, followed by an enumeration of the leading 
difficulties in the way of their acceptance ; diffi- 
eulties which would appear to be insurmountable 
to Professor Kolliker, inasmuch as he proposes to 
replace Mr. Darwin’s Theory by one which he 
terms the “ Theory of Heterogeneous Generation.” 
We shall proceed to consider first the destructive, 
and secondly, the constructive portion of the 
essay. 
1 Die Radiolarien: cine Monographie, p. 231. 
VOL, II G 
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