The family is conceived here in the sense of A. P. de Candolle, Prodr. 3 : 321 (1828), i.e. including the group of arboreous non-lianescent genera known as tribe Paropsieae, as well as the group of generally lianescent genera provided with tendrils, the present tribe Passifloreae. Most British authors, from J. D. Hooker, G. P. 1 : 810 (1867) onwards, also included the paropsiaceous genera in Passifloraceae.For various reasons tribe Paropsieae was formerly included in Flacourtiaceae by several German authors. Recent investigations have shown that the tribe fits best in Passifloraceae, as pointed out by the author in Blumea 19 : 99–104 (1971). Tribe Paropsieae is almost confined to Africa, and contains 6 small genera, of which 3 occur in the Flora area. Tribe Passifloreae is composed of 12 genera, distributed over the Old and New Worlds. Passiflora is the largest genus with about 370 species, about 350 in America, and about 20 in Australasia; it is not represented in Africa, but two species, P. foetida L. and P. suberosa L. are locally established introductions, quite often found in ruderal or otherwise disturbed places. Several other Passiflora species are introduced as ornamentals (e.g. P. mollissima (Kunth) Bailey) or for the edible fruits (P. edulis Sims and others), and these occur quite often as garden escapes. Though not indigenous to the Flora, the genus Passiflora is entered in the key. Under the genus description a key to the species occurring in the Flora area is given, and the most commonly encountered species are treated fully. The second largest genus is Adenia, mainly represented in Africa and Madagascar, and with comparatively few species in Indo-Malesia. The genus Basananthe, with 25 species, is confined to tropical Africa. The remaining genera are monotypic, or contain but a few species, and are all more or less local. For a review of the family (excluding Paropsieae) see Harms in E. & P. Pf., ed. 2, 21 : 470–507 (1925). The American representatives of the family are extensively treated by Killip, Field Mus. Nat. Hist. Chicago, Bot. 19 : 1–613 (1938); Contr. U. S. Nat. Herb. 35 : 1–23 (1960). A treatment of the family for the Malesian area is given by de Wilde in Fl. Males., ser. 1, 7 : 405–434 (1972). A monograph of the genus Adenia, including many general aspects of the family, is published in Meded. Landbouwhogeschool Wageningen 71–18 : 1–281 (1971); an account of the Old World Passifloras in Blumea 20 : 227–250 (1972), and of the genus Basananthe in Blumea 21 : 327–356 (1974). For the delimitation of genera in tribe Passifloreae see de Wilde, Blumea 22 : 37–50 (1974). Many members of the family are toxic. Among the toxic constituents are cyanogenic glucosides and for example a toxalbumine, called modeccine, reported from the fruits of Adenia (Modecca) digitata. Other species with highly poisonous fruits are A. volkensii and A. scheffleri. See also Watt & Breyer-Brandwijk, Medic. & Pois. Pl. S. & E. Afr., ed. 2 : 826–830 (1962); Verdcourt & Trump, Common Poisonous Pl. E. Afr. : 37 (1969).