ORDER CXX. TYPHACE.E CAT-TAIL-TRIBE. ORDER CXXI1. NAIADACE.E POND-WEED-FAMILY. 



201 



2. C. 



Ethiopian Calla. 



Acaulescent; leaves sagittate, cordate at base, on long, sheathing petioles, 

 shining green, very large and smooth ; spathe cucullate, convolute at base, re- 

 curved, abruptly long-acuminate, very large, bright white, about twice as long 

 as the yellow spadix. A fine plant, common in house cultivation, and much ad- 

 mired for its large, white spathe. Scape 2 4 ft. high. Jan. May. 



4. ACOEUS. 



Spathe none ; spadix lateral, sessile, densely flowered. Flow- 

 ers perfect. Sepals 6. Stamens 6. Anthers reniform. Stigma ses- 

 sile, minute. Ovaries 2 3-celled, becoming dry and few-seeded. 

 Per. 



1. A. Calamus. Sweet Flag. 



Ehizoma creeping; leaves long, ensiform, light green; scape long, ensiform, 

 resembling the leaves, bearing the sessile spadix on its edge, just above the 

 middle ; spadix covered with yellowish-green flowers. A common plant in 

 wet grounds. The aromatic pungency of the thick and creeping rhizomas is 

 well known. The scape and leaves are 2 3 ft. high, distinguished by their 

 light-green color, and the central ridge extending the whole length. June 

 Jidy. 



5. SYMPLOCARPU8. 



Spathe ventricose, cucullate, acuminate, with an incurved 

 point, fleshy, decaying soon after flowering. Spadix pedunculate, 

 oval, entirely covered with the perfect flowers. Sepals 4, cucul- 

 late, persistent, at length thick and spongy. Stamens 4. Style 

 4-angled. Stigma minute. Seeds large, globular, imbedded in the 

 enlarged, spongy spadix. 



1. S. fcetidus. Skunk-Cabbage. 



Acaulescent ; leaves ovate, cordate at base , acute, on short petioles, at length 

 very large ; spadix preceding the leaves, enveloped in a spathe, striped with 

 purplish-brown; floweis crowded on the spadix, dull-purple. A very common 

 plant in swamps and wet meadows, sufficiently marked by its well-known of- 

 fensive odor, resembling that of a skunk. Its spotted spathes appearing just 

 above the surface, are among the first evidences of approaching spring. The 

 clustered leaves soon become very large, being 10' 12' broad, and somewhat 

 longer. March April. 



ORDER CXX. Typhacese. Cat-tail-tribe. 



1. TYPHA. 



Flowers in a long, terminal, cylindrical spike, upper part sta- 

 minate. Stamens intermingled with hairs, with 3 anther%on a 

 common filament. Ovaries below, pedicellate, surrounded by nu- 

 merous bristles, forming a sort of pappus to the seed. Per. 



1. T. latifolia. 



Cat-tail. 



Stem erect, simple; rhizoma creeping; leaves ensiform, nearly flat; barren 

 and fertile spikes contiguous, mostly forming one long, compact, cylindrical 

 spike, turning brownish in fruit A common plant in swamps, distinguished 

 by its long-ensiform leaves, and its long, brown spikes. Stem 35 ft. high. 



July. 



2. SPAKGANIUM. 



Flowers in separate, globose heads, with leafy bracts ; upper 

 ones barren, consisting of stamens alone, mingled with small 

 scales ; lower fertile ; ovaries surrounded by 3 6 calyx-like 

 scales. Fruit turbinate, 1 2-celled, 1 2-seeded. Per. 



1. S. ramosum. Burr-reed. 



Stem erect, branching above; leaves linear, triangular at base, with concave 

 sides; flowers in globular clusters, resembling burrs, of a whitish-green, lowest 

 mostly pedicellate ; stigma linear, longer than the style, often 2. A common 

 plant, with somewhat grassy leaves and a reedy stem, 23 ft. high, and, like 

 the other species, distinguished by its globular burrs of flowers. It grows 

 around ponds and in ditches. July Aug. 



2. S. Americanum. 



Small Burr-reed. 



Stem erect, nearly or quite simple ; leaves nearly equalling the stem, trian- 

 gular at base, with flat sides ; fertile heads 2 4, sessile ; stigma oblong, oblique, 

 scarcely half the length of the style. A smaller and more slender species, com- 

 mon along streams and the borders of ponds. Stem 12 ft. high. Aug. 



26 



ORDER CXXII. 



Naiadaceso. Pond-weed- 

 family. 



SYNOPSIS OF THE GENERA. 



* Flowers perfect. 



2. KUPPIA. Flowers 25, on a slender, pedunculate spadix. Perianth 

 none. Stamens 2, each with 2 distinct anther-cells. 



3. POTAMOGETON. Flowers in more or less dense, pedunculate spikes. Se- 

 pals 4. Stamens 4, with 2-celled anthers. 



* * Flowers monoecious or dioecious. 



1. NAJAS. Flowers axillary, solitary. Stamen 1, furnished with a little 

 spathe. 



1. NAJAS. 



Flowers monoecious or dioecious, axillary, solitary. Barren 

 flowers stamen 1, enveloped in a little spathe. Fertile style 

 1, short; stigmas 2 4-subulate; ovary 1. Achenium 1-seeded, 

 inclosed in a loose, and easily separated membranous sheath. 



1. N. Canadensis. 



Water Nymph. 



Aquatic; stem very slender, dichotomously branched; leaves opposite or 

 whorled, very narrowly linear, sheathing at base; flowers minute, axillary. A 

 very slender plant, growing in tufts wholly under water. Common in ponds 

 and slow waters. Stem 5' 20' long. July Sep. 



2. RtTPPIA. 



Flowers perfect, 2 or more together on a slender spadix, 

 whose peduncle is much elongated and filiform in fruit, proceed- 

 ing from the sheathing base of the leaves. Perianth none. Sta- 

 mens 2, each with 2 large, separate anther-cells. Ovaries 4, 

 sessile. Achenia 4, pedicellate. Per. 



1. R. marftima. Ditch-grass. 



Marine-aquatic; stems filiform, dichotomously branching, floating; leaves 

 linear, very long and narrow, with an inflated, sheathing base, immersed ; pe- 

 duncles of the fruit capillary, 1' 2' long. A very slender, grass-like plant, 

 common in the shallow waters of bays. Stems 2 5 ft. long. The flowers ex- 

 pand at the surface. June Aug. 



8. POTAMOGLfcTON. 



Flowers perfect, spicate. Sepals 4. Stamens 4. Anthers 2- 

 celled. Ovaries 4. Achenia 4, sessile, flattened on the inner 

 side, floating aquatics. Per. 



* Leaves partly floating and partly immersed. 



1. P. natans. Broad-leaved Pond-weed. 



Stem nearly or quite simple ; upper leaves ovate or broadly elliptical, vary- 

 ing to oblong-lanceolate, rounded or cordate at base ; immersed ones lanceolate, 

 linear or capillary, all on long petioles ; spike of purplish flowers raised above 

 the water. A common aquatic, distinguished from the following species of this 

 section by its long petioles, and its simple, rather stout stems and large floating 

 leaves, 2' 3' long. The immersed leaves are sometimes reduced by decay to 

 mere petioles. Ponds and slow waters. July Sep. 



2. P. heterophyllus. Various-leaved Pond-weed. 



Stems slender, mostly branched below ; upper leaves oval, oblong or wedge- 

 lanceolate, on long petioles; immersed ones lanceolate, varying to narrow- 

 linear, or even capillary ; lower ones sessile ; spikes cylindrical, somewhat 

 loose, on long peduncles thicker than the stem. A much more delicate species 

 than the preceding, and quite variable in its forms. Common in shallow, stag- 

 nant, and slow waters. July Aug. 



3. P. hybridus. Slender Pond-weed. 



Stems branching below, very slender ; floating leaves oval or oblong-lanceo- 

 late on petioles scarcely as long as the lamina; immersed leaves capillary; spike 

 few-flowered, somewhat globular, on a very short peduncle. A very slender 

 and delicate species, growing in water 1 2 ft. deep. Common. July. 

 * * Leaves all immersed and similar. 



4. P. lucens. 



Shining Pond-weed. 



Stem branching ; leaves oval-lanceolate, large, flat, acuminate, tapering at 

 base to a very short petiole, thin and shining, especially when dry; spike 

 crowded with greenish flowers, on a long peduncle thickened upwards. A 

 common species in ponds and deep rivers, distinguished by the large and long 

 leaves varying in length 2' 5', or even more. July Aug. 



