LEMNACE^. (duckweed FAMILY.) 551 



and a cluster of very large aud broad entire veiny leaves, preceded in earliest 

 spring by the nearly sessile spathes, which barely rise out of the ground. 

 (Xanie from arv/jiirXoK-f], connection, and Kapiros, fruit, in allusion to the coales- 

 cence of tlie ovaries into a compound fruit.) 



1. S. fdetidus, Salisb. Leaves ovate, cordate, becoming 1-2° long, short- 

 pet ioled ; spatlie spotted and striped with purple and yellowish-green, ovate, 

 incurved; fruit (in autumn) 2-3' in diam., in decay shedding the bulblet-like 

 seeds, which are 4-6" long. — Bogs and moist grounds, X. Scotia to N. C. 

 west to Minn, and Iowa. 



5. ORONTIUM, L. Golden-club. 



Spathe incomplete aud distant, merely a leaf-sheath investing the lower part 

 of the slender scape, aud bearing a small and imperfect bract-like blade, 

 flowers crowded all over the narrow spadix, perfect ; the lower with 6 con- 

 cave sepals and 6 stamens ; the upper ones with 4. Filaments flattened ; an- 

 thers 2-celled, opening obliquely lengthwise. Ovary 1-celled, with an anatropous 

 ovule; stigma sessile, entire. Fruit a green utricle. Seed without all)umen. 

 Embryo thick and fleshy, " Avith a large concealed cavity at the summit, the 

 plumule curved in a groove on the outside." {Torr.) — An aquatic perennial, 

 with a deep rootstock, long-petioled and entire oblong and nerved floating 

 leaves, and the spadix terminating the elongated scape ; its rather club-shaped 

 emersed apex as thick as the spadix. (Origin of the name obscure.) 



1. O. aquaticum, L. — Ponds, Mass. to Fla. May. 



6. A C O RXJ S, L. Sweet Flag. Calamus. 



Spadix cylindrical, lateral, sessile, emerging from the side of a simple 2-edged 

 scape which resembles the leaves, densely covered with perfect flowers. Se- 

 pals 6, concave. Stamens 6; filaments linear ; antliers kidney-shaped, 1-celled, 

 opening across. Ovary 2 - 3-celled, with several pendulous orthotropous ovules 

 in each cell ; stigma minute. Fruit at length dry, gelatinous inside, 1 -few- 

 seeded. Embryo in the axis of albumen. — Pungent aromatic plants, espe- 

 cially the thick creeping rootstocks {calamus of the shops), which send up 2- 

 edged sword-like leaves, and scapes somewhat like them, bearing the spadix on 

 one edge ; the upper and more foliaceous prolongation sometimes considered as 

 a kind of open spathe. ("A/copas, the ancient name, of no known meaning.) 



1. A. Calamus, L. Scape leaf-like aud prolonged far beyond the (yel- 

 lowish-green) spadix. — Margins of rivulets, swamps, etc., N. Scotia to Fla=j 

 west to Minn., Iowa, and E. Kan. 



Order 124. LEMNACE^E. (Duckweed Family.) 



Minute stemles$ plants, floating free on the water, destitute of distinct 

 stem and foliage, being merely a frond, producing one or few monoecious 

 flowers from the edge or upper surface, and commonly hanging roots from 

 underneath; ovules rising from the base of the cell. Fruit a 1- 7-seeded 

 utricle. Seed large ; the apex or radicular extremity of the seed-coat sepa- 

 rable as an operculum or lid (as in Cabomba, etc.). Embryo straight, sur- 

 rounded by fleshy or sometimes very scanty albumen. — The simplest, and 



