VIEWS ON EVOLUTION 67 



dealing with the possible genetic relation of living to fossil 

 species, he still regards the question as more or less open. 

 Although fossil species are mostly different from living 

 species are we therefore to conclude, he asks, that they are 

 not the ancestors of the present day forms ? " The contrary 

 idea arises more naturally in the mind ; for otherwise the 

 six-days' creation would have had to be repeated and new 

 beings produced by a fresh creation. Now this proposition, 

 contrary as it is to the most ancient historical traditions, is 

 inadmissible" (p. 210). It is sufficiently clear from this 

 quotation that Geoffrey was thinking only of a transformation 

 of the antediluvian species created by God, and by no means 

 of an evolution of all species from one primitive type. In 

 matters of religion Geoffroy was orthodox. He goes on to 

 point out how great a resemblance there is in essential 

 structure between fossil and living species. All find their 

 place in one scheme of classification ; does it not seem that 

 all are modifications " of one single being, of that abstract 

 being or common type, which it is always possible to denote 

 by the same name?" (p. 211). This type is abstract, not 

 actual, and it is certainly not conceived as an original 

 ancestor of all animals. 



The fullest development of Geoffrey's views on evolution 

 is found in his memoir " Le degre d'influence du monde 

 ambiant pour modifier les formes animales." 1 Here the 

 relation of his evolution-theory to his morphology is pointed 

 out. The principle of unity of plan and composition cannot 

 be the final goal of zoology ; there must follow on it a 

 philosophical study of the differences between organic forms. 

 The causes of these differences are to be found in the 

 environment (pp. 66-7). Geoffroy seems here to be moving 

 from a pure to a causal morphology. It is probable, he 

 continues, that living species have descended by uninterrupted 

 generation from the antediluvian species (p. 74), and that 

 they have in the process become modified through external 

 influences. 



Now of all functions respiration is the most important, 

 and upon respiration everything is regulated. " If it be 

 admitted that the slow progression of the centuries has 

 1 Mem. Acad. Sa'., xii., pp. 63-92, 1833. 



