4o6 



INDEX. 



OBSERVING. 

 Observing, pleasure of, ii. 341. 

 Oceanic islands, ii. 162 ; volcanic, ii. 



76. 

 Oceans and Continents, permanence 



of, iii. 247. 

 Oceans, antiquity of, ii. 76. 

 Octopus, change of colour in an, i. 



235- 



Ogle, Dr. W., letters to :— on Hippo- 

 crates and Pangenesis, iii. 82 ; on the 

 expression of the emotions, iii. 141, 

 142, 143 ; on his translation of 

 Aristotle ' On the parts of Ani- 

 mals,' iii. 251 ; on Kerner's ' Flowers 

 and their Unbidden Guests,' iii. 287. 



on the fertilisation of Salvia, iii. 



278. 



Old Testament, Darwinian theory 

 contained in the, i. 86. 



Oliver, Prof., letter to, on the ' Fer- 

 tilisation of Orchids,' iii. 270 note. 



Ophrys apifera, observations on, iii. 263. 



Opinion, progress of, ii. 355, 356 ; in 

 Germany, ii. 357. 



Opuntia nigricans, seedling, movement 

 in, iii. 330. 



Orang Utang, G. Rolleston on the 

 brain of the, ii. 363. 



Orchids, bee and spider, possible iden- 

 tity of the, iii. 276 ; fertilisation of, 

 bearing of the, on the theory of Natural 

 Selection, iii. 254 ; fertilisation of, 

 work on the, ii. 357 ; homologies of, 

 iii. 264 ; study of, iii. 262, 263, 264 ; 

 usefulness of modifications of, iii. 

 32 ; pleasure of investigating, iii. 288. 



Orchis pyramidalis, adaptation in, iii. 

 262, 263. 



Orders, thoughts of taking, i. 171. 



Organism, Dr. Roux on the struggle 

 between the parts of the, iii. 244. 



Organs, rudimentary, iii. 119; rudi- 

 mentary, comparison of with un- 

 sounded letters in words, ii. 208 ; 

 struggle between the, in the same 

 organism, iii. 244. 



Origin of Species, first notes on the, 

 i. 68 ; investigations upon the, i. 82- 

 85 ; progress of the theory of the, ii. 

 I-114 ; differences in the two editions 

 of the ' Journal ' with regard to the, 

 ii. 1-5 ; extracts from note-books on 



ORNITHORHYNCHUS. 

 the, ii. 5-10 ; first sketch of work on 

 the, ii. 10; essay of 1844 on the, ii. 

 11-16. 



' Origin of Species,' publication of the 

 first edition of the, i. 86 ; ii. 205 ; suc- 

 cess of the, i. 8j; reviews of the, in the 

 Athenceum, ii. 224, 228 ; in the ' Na- 

 tional Review,' ii. 240, 262, 265 ; in 

 'Macmillan's Magazine,' ii. 238, 239, 

 299 ; in the Times, ii. 252, 253, 254, 

 255 ; in the Saturday Review, ii. 260 ; 

 in the Gardeners' Chronicle, ii. 267; in 

 the ' Annals and Magazine of Natural 

 History,' ii. 284, in the 'American 

 Journal,' ii. 286 ; in the Spectator, ii. 

 296, 297 ; in the ' Bibliotheque Uni- 

 verselle de Geneve,' ii. 297; in the 

 ' Medico-Chirurgical Review,' ii. 299, 

 301; in the 'Westminster Review,' 

 ii. 300 ; in the ' Edinburgh Review, ' 

 ii. 300, 302, 303, 304, 311, 313 ; in 

 the 'North American Review,' ii. 

 304, 305 ; in the New York Times, 

 ii. 305 ; in the ' Revue des Deux 

 Mondes,' ii. 305; in the 'North 

 British Review,' ii. 311, 315; in 

 ' Fraser's Magazine,' ii. 314, 315, 

 327; in the Christian Examiner, ii. 

 318, 319 ; in the ' Quarterly Review,' 

 ii. 324, 327, 331 ; in the 'London 

 Review,' ii. 328 ; in the ' Highland 

 Agricultural Journal,' ii. 331 ; in the 

 ' Geologist,' ii. 362 ; in the Dublin 

 Hospital Gazette, ii. 375 ; in the 

 ' Zoologist,' ii. 376. 



' Origin of Species,' publication of the 

 second edition of the, ii. 256. 



, third edition, commencement 



of work upon the, ii. 352, 354 ; pub- 

 lication of the, ii. 362; 



-, publication of the fourth edition 



of the, iii. 42, 43. 



-, publication of the fifth edition 



of the, iii. 108, 109. 



-, sixth edition, preparation of 



the, iii. 144 ; publication of the, iii. 

 152. 

 , the ' Coming of Age,' of the, 



111. 240. 

 Ornaments of male animals, iii. ill, 112. 

 Ornithorhynchus, ii. 143, 335, 340 ; 



mammary glands of, ii. 214. 



