-proportion of annuals.
-species of plants common to America, Chili and.
-stocked from Antarctic land.
-colonising of.
-glacial action in.
-mountain-rat of.
-trees of.

Newton, Prof. A., note on Strickland by.
-description of partridge as agent in dispersal of seeds.

Newton's law of gravity.

Niagara, Darwin on Lyell's work on.

Nightingale, Gould on the.

Noises, observations on children's.

Nolana prostrata, Darwin's experiments on.

Nomenclature, discussion on.

"North British Review," Fleeming Jenkin's review in.
-Tait in.

Norton, Professor Charles Elliot: of Harvard, the son of the late Dr.
Andrews Norton, Professor of Theology in the Harvard Divinity School.
-visits Down.

Norway, Von Buch's travels in.
-Blytt on flora of.

Norwich, Berkeley's address at British Association (1868) meeting at.
-Hooker's address.

Nottingham, British Association meeting (1866) at.
-Hooker's lecture on insular floras at.

Notylia, F. Muller on.

Nucula, a persistent type.

Nuneham, Darwin's recollection of trip to.

Nutrition, influence of mind on.

Nyctitropic movements, see Sleep-movements.

Observation, spirit of astronomers in.
-harder work than generalisation.
-pleasure of.

Observations, not to be trusted without repetition.

Observer, a good theoriser makes a good.

Oceanic islands, difference in floras and means of stocking.
-connection between continents and.
-former extension of.
-Reade on.
-volcanic nature of.

Oceans, age and depth of.
-permanence of.
-as sinking areas.

Ogle, W., on the sense of smell.
-letter to.
-translation of book by Kerner.

Ogleby, reference to his nomenclature scheme.

Oken, on Lepas.
-Owen on.

Old characters, reappearance of.

Oldenburgia.

Oldenlandia.

Olfers.

Oliver, D., Darwin indebted to for information.
-letters to.
-mentioned.

Olyra, sleep-movements of.

Omori, Morse on shell-mounds of.

Oncidium, J. Scott's work on.
-structure of labellum.
-O. flexuosum, observations by Muller and Scott on.
-self-sterility of.
-O. sphacelatum, Scott on fertilisation of.

Ophrys.
-O. apifera, fertilisation-mechanism.
-self-fertilisation of.
-O. arachnites, fertilisation of.
-habitat.
-O. aranifera.
-O. morio, fertilisation of.
-O. muscifera, Lord Farrer's observations on.
-O. scolopax.

Opossums.

Oppel, service to geology.
-mentioned.

Opuntia, Henslo