INDEX. 
Acapremy of Science at Pe- 
tersburg, 351. 
Adanson, remarks on_ his 
works upon botany and 
zoology, 79. 
Elian, 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- 
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, 
175. 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- 
tional, 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, 251. Appendages of the 
head, 253. Characters from 
caudal appendages, 255. 
Characters of, founded on 
the structure of the mouth, 
259. Suctorial animals, 263. 
Value of distinctions de- 
rived from the organs of 
locomotion, 264. Progres- 
sion of molluscous ones, 275. 
Aristotle, 5. 
GG 4 
