t>8 SPARGANIACEAE (BUR-REED FAMILY; 



1. T^THA [Tourn.] L. CAT-TAIL FLAG 



Flowers in a long and very dense cylindrical spike terminating the stem ; 

 the upper part consisting of stamens only, inserted directly on the axis, and 

 intermixed with long hairs ; the lower part consisting of stipitate 1-celled ova- 

 ries, the stipes bearing club-shaped bristles, which form the copious down of 

 the fruit. Nutlets minute, very long-stalked. Spathes merely deciduous 

 bracts, or none. Rootstocks creeping. Leaves long, sheathing the base of 

 the simple jointless stems, erect, thickish. Flowering in summer. (Ttf^i;, the 

 old Greek name.) 



1. T. latifblia L. (COMMON CAT-TAIL.) Stout and tall (1-2 m. high), the 

 flat sheathing leaves 6-23 mm. broad, exceeding the stein ; the staminate and 

 dark brown pistillate parts of the spike (each 8-15 cm. long or more) usually 

 contiguous, the latter at length 2.5 cm. in diameter ; pistillate flowers without 

 bractlets ; stigma rhombic-lanceolate; pollen-grains in fours. In marshes, 

 throughout temperate N. A. (Cosmop.) 



2. T. angustifolia L. Leaves narrower (6-12 mm. broad), somewhat con- 

 vex on the back ; pistillate and staminate parts of spike usually separated by a 

 short interval, the fertile portion becoming 10-12 mm. in diameter ; pollen- 

 grains simple ; pistillate flowers with a linear stigma and a hair-like bractlet 

 slightly dilated at the summit. S. Me. to N. C. and westw., less frequent than 

 the preceding, and mainly near the coast. (Eurasia, etc.) 



SPARGANIACEAE (BUR-REED FAMILY) 



Marsh or aquatic plants with alternate sessile linear 2-ranked leaves and 

 monoecious flowers in globular sessile or pedunculate heads. Upper heads bear- 

 ing sessile 3-androus naked flowers and minute scales irregularly interposed. 

 The lower heads consisting of numerous sessile or shortly pediceled pistillate 

 flowers with a calyx-like perianth of 3-6 linear or spatulate scales. Ovary 

 1-2-celled. Fruit obovoid or spindle-shaped, 1-2-seeded. 



1. SPARGANIUM [Tourn,] L. BCR-REED 



Heads scattered along the upper part of the simple or sparingly branched 

 leafy stem, the bracts caducous or the lower persisting and leaf-like. Perennials 

 with fibrous roots and creeping horizontal rootstocks. Flowering through the 

 summer. The fertile heads becoming bur-like from the divergent beaks, but 

 the pistils at maturity falling away separately. (Name ancient, probably from 

 <rirdpya.vov, a band, in allusion to the ribbon-like leaves.) 



Fertile flowers closely sessile ; fruit broadly obovoid 1. S. eurycarpum, 



Fertile flowers shortly pedicellate ; fruit fusiform. 

 Beak of fruit long and slender ; stigma linear. 

 Pistillate heads strictly axillary. 



Mature fruits dull ; "stigma 1-2 mm. long 2. S. amer-icanum. 



Mature fruits lustrous ; stigma 2.5-4 mm. long 3. S. lucidum. 



One or more of the pistillate heads supra-axillary. 



Erect plants of muddy shores ; leaf-blades translucent and reticulated 4. S. dirertiifolium. 

 Distinctly aquatic ; leaves with long floating opaque blades. 

 Acbenes rather abruptly slender-beaked : leaf-blades 1.5-4 mm. 



broad; stigma rarely over 1.2 mm. long 5. S.angutifolium 



Achenes gradually acuminate ; leaf-blades 4-9 mm. broad ; stigma 



1.5-2 mm. long 6, S. simpler. 



Beak of fruit stouter and falcate or short and conical or none ; stigma ovoid or oblong. 

 Fruiting heads 2 cm. in diam. ; beak gladiate-falcate . . . .7. S.Jluctuans. 

 Fruiting heads 1 cm. in diam. 



Beak short, conical 8. S. minimum. 



Beak none, stigma sessile 9. S. /iyj>frbi>renm. 



1. S. eurycdrpum Engelm. Stems stout, erect (8-13 dm. high) ; leaves mostly 

 flat and merely keeled ; pistil attenuate into a short style bearing 1 or 2 elongated 

 stigmas ; fruit heads 2-6 or more, 2-3 cm. in diameter ; fruit angled, often 



