3. Typha domingensis Pers. TuLE. Fig. 26. 



Plant slender, to about 3 m. tall, the stem pith white; leaves 6 to 10, usually 

 flat, yellowish-green, firm or coriaceous, 7-15 mm. wide, usually shorter than the 

 inflorescence; sheaths tapering at throat to the blade, scarious-margined above; 

 staminate portion of spike 2-4 dm. long, more or less separated (sometimes by 

 as much as 6 cm.) from the whitish-brown pistillate portion; surface of spike 

 similar to that of T. angustifolia; stigmas linear, interspersed with many apiculate- 

 bladed bractlets, soon deciduous; compound pedicels 0.5-0.8 mm. long. T. 

 truxillensis H.B.K. 



In brackish or fresh marshes and pools throughout most of our area, Apr. -May; 

 from Fla. to Tex. and s. Calif., n. along the coast to Del. and e. Md. and inland 

 to Kan., Ut., Nev. and n. Calif.; also trop. Am. 



Fam. 14. Sparganiaceae Rudolphi Bur-reed Family 



Perennial marsh or aquatic monoecious plants with horizontal rootstocks and 

 alternate sessile 2-ranked linear leaves on an erect simple or branched stem; 

 flowers in distant somewhat regularly disposed globular sessile or pedunculate 

 heads on the upper part of the stem or its branches; upper heads bearing sessile 

 staminate naked flowers and minute scales irregularly interposed; lower heads 

 composed of numerous sessile or shortly pedicelled pistillate flowers with a calyx- 

 like perianth of 3 to 6 linear to spatulate or obovate-flabellate scales; bracts 

 caducous or the lower ones persisting and leaflike; ovary 1- to 2-ceiled; achenes 

 suborbicular to obovoid to fusiform, 1- or 2-seeded, 



A monotypic family. 



1. Sparganium L. Bur-reed 



Characters of the family. Pistillate heads becoming burlike from the divergent 

 beaks but the achenes at maturity falling separately in summer and autumn. 



About 20 species in the temperate and cold regions of both hemispheres. 



Waterfowl and marsh birds are known to eat the achenes, and muskrats eat the 

 basal parts or even the entire plant of all our species. They are also eaten by 

 deer. Their primary value, however, is as cover plants that attract marsh birds 

 and waterfowl. 



1. Mature achenes sessile, typically broadly cuneiform to obpyramidal, usually 

 more than 4 mm. thick across top, truncate to broadly rounded at 

 apex with the stout beak produced rather abruptly; stigmas usually 



2 but (in our region) 1 not uncommon; inflorescence usually 

 branched 1. S. eurycarpum. 



1. Mature achenes more or less stipitate, typically fusiform or rarely somewhat 



fusiform-obovoid, somewhat tapered at both ends, usually less than 



3 mm. thick, gradually tapered to the rather slender beak, occa- 

 sionally somewhat constricted at about the middle; stigma always 1; 

 inflorescence simple or branched (2) 



2(1). Staminate head usually single; fruiting heads to 1.5 cm. in diameter; beak 



of achene usually about 1 mm. long, rarely to 1.5 mm 



2. S. minimum. 



2. Staminate heads usually 2 or more; fruiting heads usually 2 cm. or more in 



diameter, rarely less; beak of achene 2 mm. long or more (3) 



3(2). Heads (or at least one of them) supra-axillary; distribution New Mexico 

 and Arizona (4) 



3. Heads or branches of inflorescence all axillary; distribution Oklahoma and 



Texas (5) 



89 



