INDEX. 



Academy of Science at Pe- 

 tersburg, 351. 



Adanson, remarks on his 

 works upon botany and 

 zoology, 79. 



iElian, 10. 



Affinities, discovery of the 

 circular nature of, 91. 



Affinity and analogy, doc- 

 trines of, 116. 



Albin, 32. 



Aldrovandus, Ulysses, the na- 

 turalist, remarks on his 

 works, 14. 



Analogy and affinity, theo- 

 retical distinction of, 214. 



Analogy, importance of, when 

 applied to the confirmation 

 of theory, 282. Analogy 

 between the natural and the 

 moral world, 283. Import- 

 ance of, to natural history, 

 284. Difference between 

 an argumentative and an 

 illustrative analogy, 286. 

 Interest arising from, 289. 

 General effects and advan- 

 tages produced by, in the 

 elucidation of truth, 290. 

 Three sorts of analogies, 

 291. Material and spirit- 

 ual, 293. Applicable to 

 physical science, 295. 



Animals, form and construc- 

 tion of, 167. External dis- 

 tinction preferable to inter- 



G G 



nal, 169. Internal con- 

 struction of, 171. Aids 

 afforded by anatomy, 172. 

 The properties of, 173. 

 Habits and economy of, 



174. Diversity of the 

 habits and operations of, 



1 75. Properties of, in re- 

 gard to their influence or 

 uses in the economy of 

 nature, 179. Instances of 

 analogy and affinity of, 183. 

 Contrariety of structure in, 

 illustrated, 229. Grada- 

 tion of form in, 231. Re- 

 sults of numerical equality 

 in tribes, 233. Characters 

 of natural groups, 236. 

 Universal characters objec- 

 tion al, 239. Variations of 

 character, 241. Generic 

 characters of, 243. Uni- 

 formity in natural groups, 

 245. Essential characters 

 of, 248. Simplicity of de- 

 finition, 249. General form 

 of, 25 1 . Appendages of the 

 head, 253. Characters from 

 caudal appendages, 255. 

 Characters of, founded on 

 the structure of the mouth, 

 259. Suctorial animaN. 

 Value of distinctions de- 

 rived from the organs of 

 locomotion, 264. Progres- 

 sion of molluscous one-. 



Aristotle, 5. 



4« 



