102 



FAMILIES OF FLOWERING PLANTS 



All tlie transition stages of this process may be observed in the flower 

 of the common water-lily. This genus {Casfalia) is represented in the 

 United States by several species. The flowers of C odorata are the 

 most fragrant ; in southern species the fragrance partiallj- or wholly 

 disappears. On the coast of New England, particularly on Cape Cod, 

 occurs a beautiful pink-flowered variety. The exotic Castalias, usually 

 cultivated as Nyniphaeas, exhibit a wide diversity of coloration, includ- 

 ing all shades of blue, purple and red. The yellow lotus {Nelumho 

 I idea) is common in certain parts of the country, while the pink lotus 



{N. Nelumho) has become natural- 

 ized in ponds about Bordentown, 

 New Jersey. The giant water-lily 

 of the Amazon ( Victoria regia) is too 

 well known by description to require 

 comment. 



Family Ceratophyllaceae. Horn- 

 wort family. Contains a single 

 genus, CeraiophijUnm, with three 

 widely distributed species, the most 

 familiar of which is C. demerswn. It 

 is a submerged aquatic, with capil- 

 lary or thread-like stems and leaves, 

 found frequently in slow-moving 

 streams. The flowers are without a 

 corolla, and the calyx is many- 

 parted. The fruit is an achene with 

 a long beak, and usuallj^ covered 

 with tubercles or provided with 

 spiny appendages. 



Family Trochodendraceae. Tro- 

 chodendron Family. Contains two 

 genera, CercidiphylJum, with two spe- 

 cies, and TrochodeiKlron, which is monotypic. They are Japanese trees, 

 formerly included in the Magnoliaceae, but distinguishable on account of 

 their peculiar flowers, which are entirely destitute of perianth. The 

 numerous stamens are deciduous, surrounding the 5-8-celled ovar3^ The 

 leaves are borne in whorls, a character from which the names of both 

 genera are derived. 



Family Eanunculaceae. Crowfoot or Buttercup Family. Con- 

 tains about 40 genera and over 1000 species, natives of temperate or 

 even arctic regions, remarkably scarce in the tropics. They are herbs 

 or rarely climbing shrubs, with watery and acrid juice, simple or com- 

 pound leaves, and flowers usually with both cal^'x and corolla, the 



Fig. 85. The marsh marigold {Caltha pa- 

 Insiris). After Britton 6t Brown, 111. Fl. 

 North. U. S. 



