=Supra-soriferous ferns.=--In the great majority of ferns the sori or clusters of spore cases are placed on the under surface of the fronds; nevertheless, a few cases are on record where the fructification is produced on the upper as well as on the lower surface, and sometimes abundantly so. This occasionally happens from the elongation of the normally placed sorus, which thus extends to the margin, and returns on the upper side, when the sori chance to be placed opposite to the marginal crenatures. But it is also frequently the case that the sori are produced on the upper side, distinctly within the margin, and where there are no corresponding sori beneath. Those varieties which have the margin crenated or lobed seem most liable to assume this abnormal supra-soriferous condition. Among the ferns in which this condition has been observed are the following: _Scolopendrium vulgare_, _Polypodium anomalum_, Hook., _Asplenium Trichomanes_, _Cionidium Moorei_.[189] FOOTNOTES: [147] 'Gard. Chron.' 1852, p. 51. [148] 'Flora.' 1858, pp. 32-42. [149] 'Journ. Linn. Soc.,' vol. vi; "Botany," 1862, p. 24. [150] 'Tijdschrift voor Natuur. Geschied,' 1836, vol. iii, tab. vii, p. 171. [151] Roeper, 'Enum. Euphorb.,' p. 19. Bernhardi, 'Linnaea,' vii, p. 561, tab. xiv, f. 1. Wydler, "Subcotyled. sprossbildung," 'Flora,' 1850, p. 337. Hooker, 'Trans. Linn. Soc.,' vol. xxiv, p. 20 (_Welwitschia_). [152] 'Misc. Austriac. ad Bot.,' vol. i, p. 133, t. 5. [153] See also Carriere, 'Revue Horticole,' 1866, p. 442; and as to pears, Radlkofer in 'Bericht ueber die Thaetigkert der Baierischen Gartenbau Gesellschaft,' 1862, p. 74, t. i. [154] 'Flora Indica,' p. 23. [155] 'Bull. Soc. Bot. Fr.,' 1856, p. 53. [156] 'Trans. Linn. Soc.' xxvi, p. 142, tab. iv, B. [157] "Si arbusculam, quae in olla antea posita, quotannis floruit et fructus protulit, deinde deponamus in uberiori terra calidi caldarii, proferet illa per plures annos multos ac frondosos ramos, sine ullo fructu. Id quod argumento est, folia inde crescere, unde prius enati sunt flores; quemadmodum vicissim, quod in folia nunc succrescit, id, natura ita moderante, in flores mutatur, si eadem arbor iterum in olla seritur."--Linnaeus, 'Prolepsis,' Sec. iii. [158] 'Rev. Hortic.' May, 1868, 'Gardeners' Chronicle,' 1868, pp. 572, 737. [159] Cited in 'Annals Nat. Hist.,' 1845, vol. xv, p. 177. [160] 'Ann. Scienc. Nat.,' vol. xiv, 1860, p. 13. [161] Naudin, 'Ann. Sc. Nat.,' 2nd ser., 1840, vol. xiv, p. 14, fig. 6, pl. i (_Drosera_). St. Hilaire, 'Comptes Rendus,' ix, p. 437. [162] Hance, 'Hook. Journ. Botany,' 1849, vol. i, p. 141, pl. v. [163] Booth, 'Gard. Chron.,' Jan. 1st, 1853, p. 4. [164] Lindley, 'Theory of Horticulture,' ed. 2, p. 273. [165] 'Hook. Journ. of Botany,' 1852, iv, p. 206. See also the curious _Begonia gemmipara_, 'Hook. fil. Illust. Himal. Plant.,' t. xiv. [166] 'Phytanth.,' n. 36, _d._ [167] 'Ann. Scienc. Nat.,' 3rd series. 1853. vol. xix, p. 251, tab. 14.