ception in Nymphæa, Nuphar, Butomeæ, Lardizabaleæ, ibid., 555; Hydropeltideæ, Mesembryanthemum, 556; explanation of, 556; belong to the transformed leaf, or carpel, and not derived from processes of the axis, 563; arrangement of in Cyrtandraceæ, 558; in Hydnora, Rafflesia, and Brugmansia, ibid.
Oxalideæ, distinction of the order, observation on its affinities, and on the genera composing it, 113-14
Palmæ, observations on the order and on its distribution in Terra Australis and New Zealand, 51; further observations on the order, on its distribution, and on the species found in the vicinity of the Congo, 140
Paniceæ, a tribe of Gramineæ, observations on the tribe and its distribution in Terra Australis and elsewhere, 57-8
Papaveraceæ, stigmata and placentæ of adjoining cells confluent in, 559
Papaw of the banks of the Congo, probably brought from America, 155; arguments in favour of its American origin, 158
Papilionaceæ, observations on the order, and on its distribution in Terra Australis, 21; species found in the vicinity of the Congo, 111; in Central Africa, 295
Parasites on roots, distinguishing characters of, in their leaves, seeds, and embryo, 391-2; modes of union between the stock and parasite, 392; no instance, at present, of parasites on roots originating from other parts of the plant, 395; found, however, to be the case in Rafflesia Arnoldi, 403.
Parasitism of Rafflesia discussed, 389—392; proved, 394-5; compared with Cytinus, Aphyteia, Cynomorium, and Balanophora, 391-2; mode of growth from the seed, and attachment to the stock in Rafflesiaceæ, 414 note
Park, Mungo, plants collected by him on the banks of the Gambia, 152
Parkia, characters of the genus and observations on the species composing it, 289 and note
Parnassia, stigmata and placentæ of adjoining cells confluent in, 559
Paropsia, its affinities, 121
Parry, Captain, list of plants collected at Melville Island, during the voyage of, 183, 195.
Passifloreæ, observations on, 121; regarded as forming a natural class, with Cucurbitaceæ and Homalinæ, 122; observations on the African species of, 150; compared with Rafflesia, 386-9
Paterson, Colonel, plants collected by him in New South Wales, and at Port Dalrymple, 6
Peliosanthes Teta, its seed becomes naked by the early rupture of the pericarpium, 362
Pennisetum trichotomum, a great annoyance to man and beast, 302-3
Petaloma belongs to Melastomaceæ, 118
Phænogamous plants, number of species in Persoon's Synopsis, 5; number of Australian species known [in 1814], 7; [in 1849], 338
Philydrum, observations on the genus, 53
Phyllocladus, analogy of male and female organs in, 460
Phytolaceæ, establishment of the order, observations on its structure and affinities, and on the species found in the vicinity of the Congo, 138
Pineapple of the banks of the Congo brought from America, 155
Pinus, origin of the ovulum in, 458; analogy of male and female organs in, 461; plurality of embryos in several species of, 568—572; the species of, well adapted for an investigation into the origin and development of the embryo, 569; early changes consequent on impregnation in, 569—571; separation of the amnios, 570; formation of cavity in, ibid.; development of funiculi, 577; formation of embryos, ibid.; ramification of funiculi, 577-8; each impregnated ovulum con-
