108 ORCHIDACEJE. (OECHIS FAMILY.) 



CLASS II. ENDOGENS OB MONOCOTYLEDONS. 



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

 monocotyledonous. 



ORDER 52. ALISMACE.S. 



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 6 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. maritimum, 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-jjetioled, 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. Amsricanum, Gr. Leaves longpetioled 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 plantago; the petals incisely 

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



ORDER 53. ORCHID ACE-ffiJ. 



Hnrbs with irregular 6-merous perianth adnate to the 1-celled ovary; the ovules innu- 

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

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



