ON THE METHOD OF PALAEONTOLOGY 437 



soundness of their work, — so long as they confine themselves to such 

 purely morphological questions as are involved in the restoration of 

 extinct forms. 



Nor can I find that in practice those palaeontologists who have 

 studied the Vertebrata trouble themselves much about physiological 

 correlations or adaptations to purpose. The reader of Cuvier's 

 " Ossemens fossiles " might begin at the tenth volume and read on to 

 the second, and while he would be astounded at the enormous know- 

 ledge of the laws of morphology — of the observed coexistence of parts 

 which it displays — he would find himself very rarely troubled with 

 any remarks upon physiological correlations or adaptations ; and any 

 which might offer themselves would be entirely subordinate to the 

 great object of the work, which is, to apply the purely empirical laws 

 of morphological correlation, which have been ascertained to obtain 

 among living beings, to the elucidation of fossil remains. 



It is with no little surprise, therefore, that in the first volume he 

 finds, or seems to find, the principle of physiological correlation 

 brought prominently forward, in the celebrated ' Discours sur les 

 Revolutions,' as the guide in palaeontology, as the especial means by 

 which the determination of mammalian fossils, at any rate, is effected. 

 I say, seems to find ; for, after all, if the master's words be studied 

 carefully, it will be discovered that his followers are more Cuvierian 

 than Cuvier. 



In fact, as I have already particularly pointed out, in a lecture 

 which I recently delivered before the members of the Royal Institu- 

 tion, Cuvier gives up the principle of physiological correlation, both 

 explicitly in words and implicitly in practice, as an exclusive guide in 

 paljeontological research ; and he expressly admits the necessity of a 

 reference to the laws of morphological correlation. 



But while admitting the importance of both methods, the physio- 

 logical and the morphological, he gives to the former by his words 

 a prominence which it by no means has in his practice ; or perhaps 

 I may more justly say, that his phraseology is ambiguous, from his 

 having confounded the two methods together, under the one term of 

 " principe de la correlation des formes dans les etres organises." 

 Those who will read carefully from p. 178 to p. 189 (ed. 4, 1834) 

 of the ' Discours,' will find that this confusion exists throughout. 

 Thus, if we take one of the opening passages already cited 

 (p. 178):- 



" Every organized being constitutes a whole, a single, and com- 

 plete system, whose parts mutually correspond and concur by their 

 reciprocal reaction to the same definite end. None of these parts can 



