ts, account in "Origin" of Slave-.
-Forel's work on.
-Moggridge on Harvesting-.
-F. Muller's observations on neuter.
-storing leaves for plant-culture.

Apathus, living in nests of Bombus.

Apes, comparison as regards advance in intellect between man and.
-ears of anthropoid.

Aphides, absence of wings in viviparous.

Aphis, Huxley on.

Apostasia, morphology of flowers.

Appalachian chain, Rogers on cleavage of.

Apteryx, Owen on.
-wings of.

Aquilegia, Hooker and Thomson on.
-variation in.
-peloria and reversion.

Arachis hypogaea, Darwin on.

Arachnidae.

Araucaria, abundant in Secondary period.

Araucarian wood, fossil in S. America.

Arca, Morse on.

Archaeopteryx.

Archer-Hind, R.D., translation of passage from Plato by.

Archetype, Owen's book on.
-Owen's term.

d'Archiac's "Histoire des Progres de la Geologie."
-candidate for Royal Society Foreign list.

Arctic animals, protective colours.

Arctic climate, cause of present.

Arctic expeditions, Darwin on.

Arctic floras.
-relation between Alpine and.
-relation between Antarctic and.
-Hooker's Essay on.
-Darwin's admiration of Hooker's Essay.
-migration of.

Arctic regions, few plants common to Europe and N. America not ranging
to.
-range of plants.
-northern limit of vegetation formerly lower.
-ice piled up in.
-previous existence of plants in.

Arenaria verna, range.

Argus pheasant, colour.
-unadorned head.

Argyll, Duke of, attack on Romanes in "Nature."
-rejoinder by Romanes in "Nature."
-Hooker on.
-letter to.
-"Reign of Law" by.

Aristolochia, fertilisation of.

Aristotle, reference to.

Ark, Fitz-Roy on extinction of Mastodon owing to construction of.

Armadillo.

Army, measurement of soldiers of U.S.A.

Artemia, Schmankewitsch's experiments on.

Ascension Island, plants of.
-earth-movements.
-volcanic rocks.

Ascidians, budding of.

Asclepiadeae, fertilisation of.

Ash, comparison of peat and coal.

Asher, Dr., sends Russian wheat to Darwin.

Ashley.

Ashley Heath, Mackintosh on boulders of.

Askenasy, E., on Darwinism.

Aspicarpa.

Ass, hybrids between mare and.

Asterias.

Astragalus hypoglottis, range of.

Astronomical causes, crust-movements due to.

Asturian plants in Ireland.

Atavism, use of term by Duchesne.
-Kollmann on.

Athenaeum Club, Huxley's election.

"Athenaeum," correspondence o