In a flower of a _Cyclamen_ recently examined there were ten petals in one series, the additional five being evidently due to the subdivision of the five primary ones; the natural circular plan of the flower was here replaced by an elliptical one. A similar occurrence takes place in the flowers of maples (_Acer_), which sometimes show an increased number of parts in their floral whorls and an elliptical outline. Whether the additional organs in this last case are the result of complete lateral chorisis or of multiplication proper I do not know. Orchids are very subject to an increase in the number of their labella. As illustrations may be cited an instance recorded by Mr. J. T. Moggridge in a flower of _Ophrys insectifera_, and in which there were two labella without any other visible deviation from the ordinary conformation.[400] I am indebted to Mr. Hemsley for the communication of a similar specimen in _O. apifera_, in which there were two divergent lips, each with the same peculiar markings. One of the sepals in this flower was adherent to one of the lateral petals. This augmentation of the labella depends sometimes on the separation, one from the other, of the elements of which the lip is composed, at other times on the development, in the guise of lips, of stamens which are usually suppressed (see p. 380). The following enumeration will suffice to show the genera in which an increased number of petals or perianth-segments in any given whorl most frequently occurs. Anemone! Ranunculus! Aconitum! Raphanus. Bunias. Saponaria. Dianthus! Pelargonium! Hibiscus. Fuchsia. Sarothamnus! Lotus! Ulex! Prunus! Trifolium. OEnanthe and Umbellif. pl.! Sambucus! Bryonia. Campanula. Solanum. Veronica. Cyclamen! Primula! Anagallis! Plumbago. Jasminum. Syringa! Tradescantia. Iris. Tigridia. Narcissus. Tulipa. Convallaria! Paris! Hyacinthus! Allium! Ornithogalum. Orchideae, sp. pl.! For other illustrations see multiplication of whorls, petalody; see also Moquin, loc. cit., p. 350. Engelmann, loc. cit., p. 20, Sec. 18. Cramer, loc. cit., p. 25. =Polyphylly of the androecium.=--An increased number of stamens frequently accompanies the corresponding alterations in other whorls, and seems, if anything, to be more frequent among monocotyledonous plants than among dicotyledonous ones; thus, we occasionally find tetramerous flowers in _Crocus_, _Hyacinthus_, _Tulipa_, _Iris_, _Tigridia_, &c., and more rarely in _Yucca_ (_Y. flexilis_[401]).