Pricrerk ARTICLES. 
NOTES ON NORTH AMERICAN GRASSES. VI. 
SYNOPSIS OF TRIPSACUM. 
Tripesacum L., Syst., Ed. 10, 2:1261. 1759. 
A GENUS of grasses confined for the most part to North America. The 
type species is 7. dactyloides L. 
KEY TO SPECIES. 
Staminate spikelets all sessile or nearly so, outer glume coriaceous; 
spikes single or 2- to 3-digitate. Section DACTYLOIDEs. 
Blades 4 to 5°™ wide, pubescent on upper surface. . . Jatifolium 
Blades mostly less than 2°™ wide 
Blades 1 to 3™™ wide, involute . . - . + « + floridanum 
Blades 1 to 2°™ wide, flat 
Sheaths glabrous, blades sian except sometimes 
along the midribabove. . . . . dactyloides 
Sheaths more or less hispid, or sometimes es glab- 
rous, blades hispid on upper surface dactyloides hispidum 
Staminate spikelets with one of the pair sessile, the other pedicelled, 
outer glume membranaceous; pistillate spikes branched, form- 
ing a fascicle. Section FascrcunaTa. 
Sheaths hispid . . pilosum 
Sheaths glabrous daceps ‘oe fowccstiosé: or « Miepid ‘ally at the 
throat 
Blades 3°™ or more in width, glabrous . . . fasciculatum 
Blades 2°™ or less in width, pubescent on upper surface 
1.5 to 2°™ wide, flat or folded, culms robust . .lanceolatum 
5 to ro™™ wide, more or less involute, culms 
Ct, . . « . Lemmoni 
Tripsacum latifolium, n. sp. ge ose vaginis glabris vel 
apice pubescentibus, laminis amplis, ad 4.5°™ latis, 70°" longis, planis, 
supra pubescentibus subtus scabris vel glabrescentibus, spiculis steril- 
ibus geminis sessilibus, 3-4™™ longis, oblongis, obtusis vel breviter acutis. 
Culm robust, 1°™ in diameter, glabrous; sheaths glabrous or pubes- 
cent towards apex; blades ample, as much as 7o°™ long and 4.5°™ 
Botanical Gazette, vol. 41] . [294 
