278 



NATURAL HISTORY OF ORGANIZED BODIES. 



establish tlie affinity or tlie separation of beings on the most important char- 

 acters. 



Anatomy, in the mean time, came in aid and revealed the interior structuro 

 of animals and plants. It showed that certain organs seem, from their constant 

 occurrence in the series of beings, to have on that account a predominant 

 importance, while others which are frequently modified, and sometimes wholly 

 wanting, appear to be but accessories, and of a secondary utility. Hence it is 

 that tlie presence of a vertebral canal containing the spinal marrow has furnished 

 the distinctive character of a Avhole branch of the animal kingdom, that, namely, 

 of the vertebrata. In this second phase of the evolution of the natural sciences, 

 man no longer confined himself to the role of a spectator of nature. He scru- 

 tinized and compared ; he essayed to form an idea of the general plan of th«3 

 organization of beings. The dry nomenclature had thus given place to a 

 methodical classification. 



"When Cuvier appeared, comparative anatomy was doubtless already founded. 

 Antiquity itself had learned it from Aristotle ; modern times had witnessed its 

 advancement by CI. Pen'ault and Vicq d'Azyr ; but much remained to be done 

 in order to complete the classifying of animals according to their anatomical 

 constitution. The branch of the invertebrata comprised a multitude of incon- 

 graous orders, among which new divisions were of course necessary. The 

 invertebrates were di^^ded by Cuvier into three new branches, the MoUiislcs, 

 the Articidafa, and the Zoophytes. This natural classification, based on com- 

 parative anatomy, borrowed the distinctive characters from the arrangement of 

 the most important organs in the animal : from that of the nervous system. 



It was now that, combining in a comprehensive synthesis particular facts in 

 order to derive from them general ideas, Cuvier was enabled to throw liglit on 

 some of the laws which govern the organized world. Such, for example, is 

 the law oi subordination of organs, which teaches us that such or such an organ, 

 when it is present in an animal, implies the presence of other organs which are 

 associated Avith it after a necessary manner. Natural history had thus become 

 a veritable science, agreeably to the definition of Bacon: "Sciences are only 

 facts generalized." Now, generalization had conducted Cuvier to the expression 

 of laws. These, in turn, led him to a remarkable consequence — to the creation 

 of paleontology. It was in conformity with his law of the correlation of fonns 

 that he reconstracted the entire skeleton of a fossil animal when possessed of 

 but a few of its remains, and restored for science generations of beings which 

 had long disappeared from the surface of the globe. 



By the side of Cuvier another grand historical figure presents itself in Geoffroy 

 Saint Hilaire, his cotemporary and friend, more recently his scientific adversary. 

 Prepossessed by his labors in the natural classification of beings, Cuvier had 

 bent his whole force to the discovery of the differences Avhich separated them. 

 The genius of Geoffi'oy disposed him rather to comparison ; resemblances 

 attracted him more strongly than difierences, and enabled him to detect, in the 

 zoological series, the imity of plan amidst the diversity of details. History 

 "will preserve the remembrance of the memorable conflicts of these illustrious 

 adversaries, conflicts which powerfully developed two great conceptions in which, 

 at last, there is nothing irreconcilable. From this epoch dates the rise of 

 anatom ical pliihsoplnj. 



While zoology was establishing itself on foundations really scientific, botany 

 had been pursuing a parallel career. As early as the XVIIth century, Pierre j\[ag- 

 nol attempted to substitute for the ancient nomenclatures a natural classification. 

 He sought, in 16S9, to distinguish plants according to their principal organs — 

 the roots, the stems, the flowers, tlie seeds. But vegetable anatomy was too 

 little advanced to pennit a classification based on the constitution of the most 

 important organs of plants. Botany had still to pass through the artificial 

 cla' ifications of Touruel'ort and Linnaeus before arriving at the more perfect 



