76 ETIENNE GEOFFROY SAINT-HILAIRE 



manifest tendency to resemble one another, and to reproduce 

 invariably the same primordial type." l Unity of plan and 

 composition is, on this view, prior to adaptation and limits 

 adaptation. Cuvier's view, on the contrary, is that the 

 necessity of functional and ecological adaptation accounts 

 for the repetition of the same types of structure. There are, 

 of all the possible combinations of organs, only a few viable 

 types those whose structure is adapted to their life. There- 

 fore it is reasonable that these few types should be repeated 

 in innumerable exemplars. One must remember, in order 

 to appreciate Cuvier's view, that he was not obsessed, as we 

 are, by the idea of evolution. 



Cuvier thought in terms of organs, not in terms of 

 " materials of organisation." He held that the resemblances 

 between the organs of one class of animals and the organs 

 of another were due to the similarity of their functions. 

 "Let us conclude, then, that if there are resemblances between 

 the organs of fish and those of other classes, it is only in the 

 measure that there is a resemblance between their functions." 

 There are only a few kinds of organs, each adapted for a 

 particular function, and these organs are necessarily repeated 

 from class to class. "As the animal kingdom has received 

 only a limited number of organs, it is inevitable that some at 

 least of these organs should be common to several classes." 3 



Geoffroy thought in terms of " materials," of parts of 

 indefinite function, parts which might take on any function. 

 He insists upon the necessity of disregarding function when 

 tracing out the unity of composition. He considers, in 

 direct opposition to Cuvier's interpretation of structural 

 resemblance as due to similarity of function, that unity of 

 composition is the primary fact, and similarity of function 

 subsidiary. In his reply in the Mammiftres (1829) to 

 Cuvier's criticisms in the Histoirc ihitnrclle dcs l\nssons 

 (1828), he insists on the necessity of excluding function from 

 consideration in any truly philosophical treatment of com- 

 parative anatomy (Discours prel., p. 25). Cuvier held that 

 function determined structure, or at least that the necessity 



1 /'////. a nn/., ']., p. 208. 



- Cuvier and Valenciennes, Hist. ti<tf. rrissons, i., ]). 550, 1828. 



3 Cuvier and Valenciennes, he. cit., p. 544. 



