[358] 'Ephem. Nat. Cur.,' dec. 2, ann. 1, 1683, p. 68, fig. 14. [359] 'Ann. des Scienc. Nat.,' third series, vol. i, 1844, p. 292. [360] 'Flora' Feb. 4, 1858, p. 69, tab. ii, f. 3, and also 'Flora,' 1860, p. 737, tab. vii, f. 9. [361] 'Bull. Acad, Belg.,' t. xvii, p. 196, "Lobelia," p. 53, c. tab. [362] Moore, 'Nature-printed Ferns,' 8vo edition, vol. ii, p. 183. [363] 'Bull. Soc. Bot. Fr.,' 1860, vol. vii, p. 461. See also Naudin, 'Ann. Sc. Nat.,' 4 ser., t. iv, p. 5. Clos, 'Bull. Soc. Bot. Fr.,' t. iii, p. 546. [364] London's 'Magazine Nat. Hist.,' vol. ii, p. 463. [365] C. Morren, 'Bull. Acad. Belg.,' 1852, t. xix, part iii, p. 444. CHAPTER II. POLYMORPHY. Usually the several organs of the same individual plant do not differ to any great extent one from another. One adult leaf has nearly the same appearance and dimensions as another; one flower resembles very closely another flower of the same age and so on. Nevertheless it occasionally happens that there is a very considerable difference in form in the same organs, not only at different times, but it may also be at the same time. Descriptive botanists recognise this occurrence in the case of leaves, and apply the epithet heterophyllous to plants possessed of these variable foliar characters. In the case of the flower, where similar diversity of form occasionally exists, the term dimorphism is used. As these phenomena appear constantly in particular plants, they are hardly to be looked on, under such circumstances, as abnormal, but where they occur in plants not usually polymorphic, they may be considered as coming within the scope of teratology.