APPENDIX. 323 



and reappears in another, rather than change its rela- 

 tions. 



IV. The principle of the Balancement des organes, from 

 whence it results that one organ cannot be excessively 

 developed unless some other organ which is connected 

 with it becomes proportionally atrophied. The first of 

 these principles applies more particularly to teratological 

 and embryological studies, whilst the three others ought 

 always to be present in the minds of those who study 

 anatomy. 



In all these anatomical labours, Geoffroy has made 

 himself the ardent and earnest champion of the doctrine 

 of epigenesis against the doctrine of evolution, which 

 was then generally admitted, and which Cuvier himself 

 maintained ; and the very rapid progress of modern 

 science incontestably tends to confirm the view adopted 

 by Geoffrey. 



The first memoirs which he published referred to de- 

 scriptive zoology, a study to which he often returned, 

 although his habitual train of thought had led him to very 

 different researches. Among works of this kind for 

 which zoological science is indebted to him, we must not 

 omit to mention his researches on the Bats. This excep- 

 tional group among the Mammalia attracted him by its 

 very singularity, and by the difficulties which had re- 

 pulsed his predecessors. Already, in 1797, he had shown, 

 in a very remarkable memoir, that the ordinary rules of 

 classification were perfectly applicable to this group, all 

 the then known species of which he divided into dis- 

 tinctly circumscribed genera. Subsequently on different 

 occasions he resumed the same subject with marked 

 predilection, describing a great many new species, and 

 creating several genera, all of which have been adopted. 

 He has given the substance of these labours in a special 

 article in the Dictionnaire Classique cCHistoire Naturelle, 



Y 2 



