1856.] OWEN STEREOGNATHUS OOLITICUS. 7 



of this conclusion being the higher law of the correlation of animal 

 forms, as defined by Cuvier, gave me the requisite confidence in its 

 accuracy. 



Comparative Anatomy, as it was advanced by Cuvier, demonstrated 

 to him this fruitful principle of the correlation of animal forms and 

 structures. It was no a priori assumption : the founder of Palaeonto- 

 logy expressly states — " Tanatomie comparce posscdait un principe 

 — celui de la correlation des formes dans les etres organises, au moyen 

 duquel chaque sorte d'etre pourrait, a la rigueur, etre reconnue par 

 chaque fragment de chacune de ses parties *." 



If the principle be true, then in proportion as the correlations are 

 known will be the success and extent of its application. That there 

 is such a principle of correlation the most assiduous and successful 

 cultivators of Comparative Anatomy since Cuvier defined it have 

 admitted. His successor in the chair of Comparative Anatomy at 

 the Garden of Plants thus paraphrases his predecessor's definition : 

 " Doubtless there reigns throughout all the sohd pieces that enter 

 into the composition of the skeleton of a vertebrate animal, but espe- 

 cially of a mammalian one, an appreciable harmony of number, form, 

 position, proportions, — in a word, a combination which must have as 

 its result such or such a kind or pecuharity of locomotion : so that 

 one can pretty well prejudge or foresee, at least within certain bounds, 

 by a physiological knowledge, certain osteographical peculiarities and 

 vice versa -f." The consequence of the premises is here somewhat 

 lamely expressed, but the admission of the physiological principle of 

 correlation of forms is unambiguous. Something more than "certaines 

 particularites osteographiques " have been and will be foreseen 

 through the above- defined law. 



In certain instances of constant coincidences of structure, as de- 

 monstrated by Comparative Anatomy, the sufficient, i. e. recog- 

 nizable, intelhgible, or physiological, cause of them is not yet known. 

 But, as Cuvier in reference to such instances truly remarks, " Since 

 these relations are constant, there certainly must be a sufficient cause 

 for them|." 



In certain other cases Cuvier beheved that he could assign that 

 * sufficient cause,' and he selects as such the correlated structures in 

 a feline Carnivore, and in a hoofed Herbivore. The physiological 

 knowledge displayed by him in his explanation of the condition of 

 those correlations I receive as true. Its apphcation in the restora- 

 tion of the Anoplotherium and Palceotherium is exemplary. 



* Discours sur les Revolutions de la Surface du Globe, 4to, 1826, p. 47. 



t " Sans doute qu'entre toutes les pieces solides qui entrent dans la composi- 

 tion du squelette d'un animal vertebre en general, mais surtout de celui d un 

 Mammifcre, il regne une barmonie appreciable de norabre, de forme, de position, 

 de proportions, en un mot une combinaison qui doit avoir pour resultat tel ou tel 

 genre de translation, telle ou telle particularitc de locomotion ; en sorte que 1 on 

 pent assez ])ien prejuger ou prevoir, dans certains limites du moins, par une^con- 

 naissance pbysiologique, certains particularites osteographiques, et vice versa. — 

 De Blainville, Osteographie, fasc. 1. p. iiS. , • . ai 



% " Puisque ces rapports sont constants, il faut bien qu ils aient une cause sum- 

 sante." — Op. cit. p. 50. . 



