1253. In the corolla, as being the highest kind of leaf, the ribs, as the fibrous fascicles, must finally separate themselves from the leaf-substance as cellular tissue. The corolla is a double organ. 1254. In conformity with the whole structure of the plant, the ribs are placed internally, the membranes externally. 1255. The leaf-ribs, isolated and perfected as a particular organ, are the _Stamen-filaments_. 1256. The leaf-membranes, or probably the phyllodia, isolated and evolved into a particular organ, are the corolla-petals. These compose in the strongest sense the corolla. The filaments consist for the greatest part of spiral fibres, and the corolla-petals of the finest cellular tissue, which may be almost designated as granular. This then would be the rational import of the corolla and its stamen-filaments. Both are of similar production; they exhibit like substance, colour, and delicacy, with cotemporaneous development and cotemporaneous death. 1257. Not only are the ribs of the corolla, but those also of the calyx, liberated to become filaments. There are calyx-and corolla-filaments. 1258. As ribs, the filaments must stand in the middle of their petals, i. e. opposite to them. 1259. Filaments, which alternate with the parts of the corolla, are consequently calyx-filaments; such as alternate with the lobes of the calyx, or stand opposite to the petals of the corolla, are corolla-filaments. 1260. Most filaments, and consequently the calycine, are alternating in their arrangement. Most corollæ therefore have no longer strength sufficient to produce filaments. 1261. Flowers provided with opposite and alternating filaments have consequently two circles of them, as is the case in many Pinks. With the determination of the number of filaments the race has been therefore specified. 1262. The number of filaments stands in relation to the parts of the corolla; therefore three and five are the prevailing numbers. 1263. There is no absolute number in the filaments, but only one of relation. Corollæ with three petals have invariably also three filaments, and those with five of the former, the same number too of the latter. 1264. The number of filaments is always the simple or multiple of the parts of the corolla. Three calyx-or corolla-parts have 3 × 1 or 3 × n, filaments. 6 is not 6, but 3 × 2; 9 is 3 × 3; 10 is 5 × 2; 20 is 5 × 4; or 5 × 3 + 5 × 1, and so on. 1265. The filaments do not simply follow the number, but also the conjunction, position and arrest, of the corolla. They are epigynous, peri-or hypogynous. 1266. In irregular corollæ the filaments are usually abortive; as in those of the orchideous, labiate and papilionaceous plants. 1267. The arrest of the filaments usually stands in inverse relation with the corolla. In the case of a larger-sized petal the filament is small, and, on the contrary, larger in opposite parts of the corolla. ANTHERS.