670 Obdee 132.— LEMNACBJE. 



6. ORON'TIUM, L. Golden Club. (Name of doubtful origin.) 

 Spathe none ; spadix cylindric, covered with perfect flowers ; perianth 

 4 to 6-sepaled ; stamens 4 to 6 ; ovary few ; stigma sessile ; fruit a dry 

 berry or utricle, seed without albumen. — 2f Acaulescent, aquatic. Fls. 

 yellow at the summit of the scape, which thickens upwards into the 

 spadix. 



O. aqudtioum. — This interesting plant is a native of inundated banks and pools, 

 U. 8. Lvs. lanceolate, 6 to 9' by 2 to 3', smooth, of a deep green, velvet-like 

 surface above, paler beneath, on long, radical petioles. Scape thick and terete, 

 about a foot in length, closely invested by a short sheath at base, and ending in 

 ii spadix of a rich yellow color, covered with small, perfect, yellow fla. of an 

 offensive odor — ^the upper ones often tetramerous. May. 



7. ACO'RUS, L. Sweet Flag. (Gr. a, privative, and Kopq, the 

 pupil of the eye ; supposed to cure maladies of the eye.) Spadix cylin- 

 dric, covered with, flowers, and issuing from the side of a leaf-like scape ; 

 perianth 6-sepaled ; stamens 6, linear ; ovary free ; stigma sessile, min- 

 ute ; fruit dry, 3-celled, many-seeded. — 2f Herbs %yith a fleshy, aroma- 

 tic rhizome. Lvs. radical, ensiform, as well as the scape. 



A. calamus L. Summit of the scape above the spadix very long and leaf-like. — 

 Grows in wet soils throughout the U. States. The thick, prostrate, creeping 

 rhizome is highly valued for its aromatic flavor, its warm and pungent taste. The 

 long, sword-shaped leaves are readily distinguished by the ridge running their 

 whole length. The cylindrical spadix is about 3' long and 3" diam., covered 

 with small, green flowers. Jn., Jl. 



Order CXXXII. LEMNACE^. Duckmeats. 



Serbs minute, stemless, floating free upon the water, and consisting of a leaf-like 



frond, or a tuft of leaves, with one or more fibrous roots. Flowers bursting from 



tho substance of the frond, or axillary, inclosed in a spathe, the sterile consisting of 



1 or 2 stamens, the fertile of a 1-celled ovary. Fruit a utricle, with 1 or more seeds. 



Embryo straight, in fleshy albumen. Fig. 602. 



Genera 4, species 20, ]ittle aquatics, widely diflfused. They are regarded as reduced aroids, 

 and among the simplest of Phenogamous plants. 



1. LEffl'NA, L. Duck-meat. (Perhaps altered from Xififia, a 

 scale.) Sterile and fertile flowers in the same spathe, the former 2 col- 

 lateral stamens, the latter a simple, carinate ovary, with a style and 

 stigma. — (J) Herbs, consisting of a frond (stem and leaf confounded), 

 sending down from the under surface roots which hang loosely in the 

 water, and producing from the margins the spathaceous flowers. (The 

 following sections arc regarded as genera by Schleiden.) 



§ LEMNA, Schleiden. Fils, filiform. Ovule solitary. Frond with a single root Nos. 1— S 



§ TELMATOPHACE, Schl. Fils. dilated in tho middle. Ova. 2 to 7. Fronds 1-rooted. .No. 4 

 § SPIEODELA, Schl. Fils. narrowed below. Ovules 2. Frond many-rooted No. 6 



1 L. trisuloa L. Ivy -leaved Duck-meat. Fronds eUiptic-laneeolate, thin, ser- 

 rate at one extremity and caudate at the other ; roots solitary. — Floating in ponds 

 and pools of clear water. Fronds nearly J' in length, diaphanous, with a tail-like 

 appendage at base, obtuse at apex, the new ones issuing in a cruciate manner 

 from lateral fissures in the margin of the old. Root a solitary fiber, ending in a 

 sheath. Flowers very minute. Utricle sitting on the upper surface of the frond. 

 June — Sept. 



Z L. minor L. Fronds ihickish, roundish or dbovate, several conjoined ; root soli- 

 tary. — This little floating plant occurs in dense patches on the surface of stagnant 

 waters. The leaves, properly fronds, adhere 2 — 3 together, 2" in length, rather 



