Y8 BOTANY. 



■with radical leaves, equitant and sheathing at the base, and scaly heads of 

 flowers. Natives chiefly of tropical regions, having no important properties. 

 There are about six genera and seventy species. Examples : Xyris, Abolboda, 

 Philydrum. Four or five species of the typical germs Xyris are known in the 

 United States. 



Order 22. Pontederiace^, the Pond-Aveed Family. Perianth tubular, 

 colored, six-parted, more or less irregular ; aestivation circinate. Stamens 

 three to six, perigynous ; anthers introrse ; ovary free, or slightly adherent, 

 three-celled ; ovules numerous, anatropal ; style one ; stigma simple. Fruit 

 a three-celled, three-valved capsule, with loculicidal dehiscence. Seeds 00, 

 •ttached to a central axis ; testa membranous ; hilum small ; embryo straight, 

 in the axis of somewhat mealy albumen ; radicle next the hilum. Aquatic or 

 marsh plants with sheathing, parallel-veined leaves, which are sometimes 

 cordate or sagittate, and have inflated petioles. The flowers are spathaceous. 

 They are natives of North and South America, East Indies, and Africa. 

 Their properties are unimportant. There are six genera, according to Lind- 

 ley, and thirty species. The principal genera of the United States are Ponte- 

 deria, Heteranthera, Schollera, and Syena. 



Order 23. Gilliesiace^, the Gilliesia Family. Perianth six-parted, 

 sometimes five-parted by cohesion of two of the pieces, in a double row ; 

 the outer, petaloid and herbaceous ; the inner, smaller and more colored ; 

 sestivation twisted. Stamens in a double series ; outer whorl sterile, in the 

 form of a six-toothed urceolate body, or of scale-like bodies, one of which 

 forms a sort of labellum ; inner whorl of six stamens, of which three are some- 

 times sterile. Qvary superior, three-celled ; style one ; stigma simple. Fruit 

 a three-celled, three-valved capsule, with loculicidal dehiscence. Seeds nu- 

 merous, attached to the axis ; spermoderm black and brittle ; embryo curved 

 in the midst of fleshy albumen. Herbs with l^unicated bulbs, grass-like leaves, 

 ' and umbellate spathaceous flowers. Natives of Chili. Examples : Gilliesia, 

 Miersia. 



Order 24. Melanthace^e, the Colchicum Family. Perianth petaloid, 

 in six pieces, which are sometimes slightly coherent, usually involute in aesti- 

 vation. Stamens six ; anthers extrorse. Ovary three-celled : ovules nume- 

 rous ; style three-parted ; stigmas three, undivided. Fruit a three-celled 

 capsule, with septicidal or loculicidal dehiscence. Seeds with a membranous 

 spermoderm ; albumen dense, fleshy ; embryo very minute. Plants with bulbs, 

 tubers, or fibrous roots, having parallel-veined leaves, sheathing at the base. 

 The flowers are sometimes polygamous. They are natives of various parts of 

 the globe, but are most abundant in northern countries. 



Sub-order 1. UvulariecB, Bellworts. Perianth early deciduous, sepals 

 distinct, petaloid. Styles united into one at the base or throughout. Fruit a 

 three-celled few-seeded berry or loculicidal pod. Stems from small perennial 

 root stocks and fibrous roots, forking, bearing ovate or lanceolate, membrana- 

 ceous, sessile or clasping leaves, and perfect flowers ; peduncles solitary or 

 one-flowered. Examples : Uvularia, Prosartes, Streptopus. 



Stih-order 2. Cokhicece. Rhizome bulbous, dehiscence of pod septicidal. 

 Of the typical genus Colchicum, the Eui'opean species, C. autumnale {pi. 

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