PANDANACE^E ARACE.E. 533 



llowers. They are chiefly found in northern countries, and some of 

 them have acrid and bitter properties. Butomus umbettatus, Flower- 

 ing-rush, is the only British plant in the class Enneandria of Linnaeus. 

 Lindley gives 4 genera, including 7 species. Examples Butomus, 

 Limnocharis. 



c. Flowers incomplete, often unisexual, without a proper perianth, 

 or with a few verticittate scales. 



1088. Order 205. Pandanacete, the Screw-pine Family. (Mono- 

 hypog.) Flowers unisexual or polygamous, covering the whole of the 

 spadix. Perianth 0, or a few scales. Male flowers : Stamens numer- 

 ous; filaments with single anthers, which are 2-4-celled, Female 

 flowers: Ovaries 1 -celled, united in parcels; ovules solitary or 

 numerous, anatropal ; stigmas sessile, equal to the carpels in number. 

 Fruit either fibrous drupes collected into parcels, or berries. Seeds 

 solitary in the drupes, numerous in the berries; embryo at the base 

 of fleshy albumen ; radicle next the hilum. Trees or bushes, some- 

 times with adventitious roots (fig. 115, 2), long, imbricated, amplexi- 

 caul leaves, usually with spiny margins and backs. Natives of 

 tropical regions. The order is subdivided into two sections: 1. 

 Pandanese, undivided leaves and no perianth. 2. Cyclantheae, fan- 

 shaped or pinnate leaves, flowers with a few scales. There are 7 

 genera, according to Lindley, and 75 species. Examples Pandanus, 

 Freycinetia; Cyclanthus, Carludovica, Nipa. 



1089. The flowers of some of the plants are fragrant, and their seeds 

 are sometimes used as food. The juice has in some instances astrin- 

 gent properties. The species of Pandanus are remarkable for their 

 aerial roots, with large cup-like spongioles. These roots are sent out 

 regularly from all parts of their stems, and appear like artificial props 

 (fig. 115, 2). Their spermoderm has numerous raphides. Their 

 leaves are arranged in a spiral manner in three rows, and in their 

 aspect they have some resemblance to those of the pine-apple hence 

 the name Screw-pine. Pandanus Candelabra is the Chandelier-tree 

 of Guinea, and is so called on account of its mode of branching. 



1090. Order 206. Araceie, the Arum Family. (Mono-hypog.) 

 Flowers generally unisexual, rarely bisexual, enclosed within a spatha, 

 and usually on a spadix (fig. 239), having male flowers at its upper 

 part, female below, and abortive flowers between them (fig. 239, 2). 

 Perianth either 0, or in the $ flowers rudimentary and scaly. Stamens 

 definite or 00, hypogynous ; anthers extrorse. Ovary free, 1- 3- or 

 more celled; ovules solitary or numerous; style short or 0; stigma 

 simple. Fruit succulent or dry, indehiscent, one, very rarely three- 

 celled; seeds one or several; embryo in the axis of fleshy or mealy 

 albumen, sometimes with a lateral cleft for the plumule ; radicle usually 



