. Bulletin of the British Museum (Natural History) Botany. STUDIES IN THE GENUS HYPERICUML. (GUTTIFERAE) 111 subfamilies, are small and narrowly cylindric to ovoid-cylindric or ellipsoid. The longer ones may be slightly curved, especially if they are borne towards the base of the placenta; but this variation has no great taxonomic significance, despite the name of Hypericum sect. 1 (Campylosporus). In Hypericum they range from 1*5 mm long in H. bequaertii (sect. 1. Campylosporus) to 03 mm long in H. gentianoides (sect. 30. Spachium). They vary in colour from yellow-brown to red-brown or dark p
. Bulletin of the British Museum (Natural History) Botany. STUDIES IN THE GENUS HYPERICUML. (GUTTIFERAE) 111 subfamilies, are small and narrowly cylindric to ovoid-cylindric or ellipsoid. The longer ones may be slightly curved, especially if they are borne towards the base of the placenta; but this variation has no great taxonomic significance, despite the name of Hypericum sect. 1 (Campylosporus). In Hypericum they range from 1*5 mm long in H. bequaertii (sect. 1. Campylosporus) to 03 mm long in H. gentianoides (sect. 30. Spachium). They vary in colour from yellow-brown to red-brown or dark purplish brown. (c) Appendages Winged seeds occur in most Bonnetioid and Hypericoid genera with dehiscent fruit, usually in the more primitive members ( in Cratoxylum but not in Triadenum or Thornea). Their apparently primitive status would seem to give support to Corner's (1976) theory that the wing is a vestigial arillar structure (true arils occur in the Clusieae). In some species ( Cratoxylum arborescens (Vahl) Blume or Mahurea casiquiarensis Spruce) the wing surrounds the rest of the seed completely or almost so, in others ( Cratoxylum maingayi Dyer) it is confined to one side, whilst in still others ( Ploiarium alternifolium (Vahl) Melchior) it consists of terminal prolongations joined by little more than a carina. The two last-mentioned stages are found in Hypericum*, but only in the more primitive sections (Fig. 27), the wing being thin and papery and thus unlike the cartilaginous wings with a peripheral vein that occur in Cratoxylum (Plate lc). Even if the wing has been reduced to a carina or less, the seed may have apical and some- times basal prolongations ( in H. geminiflorum, sect. 4. Takasagoyd) or apiculi (cf. Plate lb). In sect. 25. Adenotrias the basal apiculate expansion has evolved into a fleshy whitish C. '' winged (terminal) C~> carunculate C ^ carinate (lateral). Fig. 27 Variation in seed appendages in Hypericum. *I have seen no seed
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