in certain species of Viscum, 380–1; deviations in the regular mode of bursting, as in Dillenia and Solanum, in several Ericinæ, in Tetratheca, Hamamelideæ, Berberideæ, several Laurinæ, and certain species of Rhizophora, 381; structure altered or disguised, as in Myristica, Canella, and several Aroideæ, in Cissampelos, Conospermum, and Synaphea, ibid.; various views of the structure in Rafflesia, 381–3; not obviously reconcileable to any hypothesis of a common type, 405 note.
Anthocleista, a genus related to Apocineæ, observations on, and its affinities, 133
Apex of the nucleus regarded as the point of impregnation of the ovulum, 453; has no organic connection with the parietes of the ovarium, 454
Aphyteia, compared with Rafflesia, structure of antheræ in, 388, 396–7, 401, 461 (see Hydnora)
Apocineæ, observations on the order, and on its distribution in Terra Australis, 37; further observations on the order, and on new genera belonging to it, found in the vicinity of the Congo, 133; no species in the collection from Central Africa, 295
Apodantheæ, a tribe allied to Rafflesiaceæ, 411 note, 424; its characters, 429
Apodanthes, its characters, 430
Apostasia, position of lateral stamina in, 499; composition of stigma in, 503; placentæ of the trilocular ovarium opposite to the three outer divisions of perianthium in, 560–1
Aquilarinæ, regarded either as a distinct familv, or as a section of Chailleteæ, 126
Arachis hypogæa, of the banks of the Congo, doubtful whether indigenous or introduced, 159; its remarkable geographical distribution, 159–60
Araucaria, origin of the ovulum in, 458; analogy of male and female organs in, 461
Areola or nucleus of the cell in Orchideæ, 511–14; in other Monocotyledonous and Dicotyledonous plants, 513
Arillus, of rare occurrence, how distinguished, 449
Arnold, Dr. Joseph, his account of the discovery and description of the gigantic flower, afterwards named Rafflesia, 370—373
Aroideæ, peculiar structure of the embryo in the seeds of certain, 365
Artocarpeæ, characters of the order, and observation on the species found in the vicinity of the Congo, 138
Asarinæ, compared with Rafflesia, 384–5, 389, 392
Asclepiadeæ, observations on the order, and on its distribution in Terra Australis, 37; on the species found in the vicinity of the Congo, 134; in Central Africa, 295; observations on the organs and mode of fecundation in, 487–543; supplementary observations on, 545–551; on the structure of the pollen mass in, 522–525; the pollen grains, 524; removal of the pollen masses from their usual place, 524; how placed in the fissures formed by the alæ of the antheræ, 525; their tubes, how produced, 525; direction of the cords to the apex of the style, 525–6; and as far as the commencement of the placenta, 526; dehiscence of pollen mass uniformly on the more rounded edge, 527; application of pollen mass of one species to the stigma of another, 528: pollen tube traced to its attachment at a definite point on the surface of the ovula, 549
Asclepias, structure of the pollen mass in various species of, 523
Asclepias phytolaccoides, pollen tubes traced to a definite point of attachment on the surface of its ovula, 549; description of the ovulum in, 549–50; changes of the ovulum in, after the insertion of the pollen tube, 550–1
Asphodeleæ, observations on the order
