108 ORCHIDACE^. (OBCHIS FAMILY.) 



CLASS II. ENDOGENS OB MONOCOTYLEDONS. 



Stems consisting of woody tissue and cellular tissue (pith) intermixed. Embryo 

 monocotyledonous. 



ORDER 52. ALISMACEiE. 



Marsh herbs, with leaves all radical, scape-like flowering stems, and (in our species) 

 perfect flowers. Sepals and petals each three and distinct. Ovaries 3 to many; distinct, 

 or, at least, separating at maturity, forming 1-2-seeded pods. Stamens from G to many; 

 anthers extrorse, 2-celled. (See ADDENDA. ) 



* Calyx and corolla colored alike, deciduous. Carpels 6, united. Leaves rush-like. 



1. TRIGLOCHIN, L. ARROW-GRASS. 



Flowers small, sessile, on a naked scape. Sepals and petals ovate, greenish-white. 

 Stamens 6, filaments short. Stigmas sessile. . 



1. T. maritinmm, L. Fruit ovoid-oblong, grooved, separating into 6 linear carpels; 

 scape surpassing the leaves, angled In salt marshes. 



* * Calyx green and persistent. Corolla white, deciduous. Carpels many, distinct (Alisma}, 

 or 8 to 10 cohering (Damsonium). Leaves long^etioled, with broad Hade. 



2. ALISMA, L. WATER-PLANTAIN. 



Flowers small, verticillate, in a panicle on a scape. The numerous ovaries becoming 

 flattened akenes, arranged in a somewhat three-sided whorl. 



1. A. plantago, L., var. Amoricanum, Gr. Leaves long-petioled ovate or oblong, 

 often cordate at the base, 3-9-nerved; scapes 1 to 4 feet high; the white or pinkish 

 petals entire, broadly-elliptical; carpels 15 to 20, obliquely obovate, channeled around the 



outer end. 



2. DAMSONIUM. 



Distinguished from Alisma chiefly by the 8 to 10 long-beaked carpels cohering by their 

 inner edges in a stellate whorl. 



1. D. Californicum, Torr. Leaves on long petioles, oblong or lanceolate, with 

 obtuse or cordate base, 2 or 3 inches long; whorls distant, G-9-flowered, on scapes 12 to 

 18 inches high; flowers twice as large as those of Alisma plantar) o; the petals incisely 

 cut at the apex; akenes 4 or 5 lines long. 



ORDER 53. ORCHIDACE-2E. 



Herbs with irregular G-merous perianth adnate to the 1-celled ovary; the ovules innu- 

 merable on 3 parietal placentae, becoming fine sawdust-like seeds. One petal, called the 

 lip, is unlike the other two. Stamens consolidated with the style forming the Column. 



