NYMPHAEACEAE 59 



VI. ORDER NYMPHAEACEAE DC. 



Literature. Knuth, 'Bl. u. Insekt. a. d. nordfr. Ins.,' pp. 20-1; Caspary, 

 in Engler and Prantl., 'D. nat. Pflanzen-Fam./ Ill, 2, pp. 1-10, Leipzig, 1888. 



The large floating flowers are protected from creeping animals by their aquatic 

 habitat, and are only accessible to flying insects. The inner side of the sepals 

 is coloured like the petals, so that both whorls are conspicuous. A more or less 

 distinct odour of honey also serves as a further attraction to insects. 



34. Nymphaea L. 



Homogamous or slightly protogynous pollen flowers with an odour of honey. 

 The stigma secretes a moisture which is, perhaps, licked by insects : according to 

 Jordan, however, there are flat nectaries in front of the stamens, in which case 

 the flowers should be placed in class EC or C. The white inner surface of the 

 sepals, and of the numerous petals which gradually pass into the stamens makes 

 the flower conspicuous. 



126. N. alba L. (Delpino, ' Ale. appunti d. geog. bot.,' Boll. Soc. geogr. ital., 

 Roma, v, 1869; Knuth, 'Bl. u. Insekt. a. d. nordfr. Ins.,' pp. 21, 148, 'Weit. Beob.,' 

 p. 231 ; Heinsius, Bot. Jaarb. Dodonaea, Ghent, iv, 1892 ; Kerner, 'Nat. Hist. PI.,' 

 Eng. Ed. 1, II, p. 218; Schulz, 'Beitrage,' II, p. 9; Watson, Justs bot. Jahresber., 

 Leipzig, xii (1884), 1886, p. 682; Caspary, op. cit.) The faintly odorous, large, 

 white flowers, which open in the morning and close towards evening, are homo- 

 gamous according to my observations. Kerner states that the stigmatic papillae 

 are mature at the beginning of anthesis, remaining receptive for several days. The 

 anthers begin to dehisce when the flower opens, or a day rarely a few days 

 later. The filaments bend into the form of a sickle, so as to bring the anthers 

 above the stigmas, which spread out into a plate-like surface, so that self-pollination 

 must result from falling of the pollen. Insect visitors may effect either cross- or 

 self-pollination, but they are few in number. The flowers are usually 10 cm. or even 

 more in diameter. In dried-up marshes, however, on the Island of Fohr, I found 

 flowers of only 5 cm. diameter, and these I have described (' Flora d. nordfr. Ins.,' 

 p. 32) as the variety terrestris. 



Visitors. On the Island of Fohr I observed a diminutive fly (Notiphila cinerea 

 Fall), freq. Heinsius in Holland noted a species of the same genus (Notiphila 

 nigricornis Stenh.). Schulz for central Germany has recorded various flies and 

 beetles. MacLeod in Flanders observed a beetle (Domicia) (Bot. Jaarb. Dodonaea, 

 Ghent, vi, 1894, p. 183). 



In Dumfriesshire (Scott-Elliot, ' Flora of Dumfriesshire,' p. 7), Apis, a humble- 

 bee, and Muscids have been observed. 



35. Victoria Lindl. 



127. Victoria Regia Lindl. The flowers, which may be as large as dinner-plates, 

 are first white, and then rose-coloured. 



Visitors. Delpino believes that the flowers are pollinated by Cetoniae and 

 Glaphyridae. 



