570 



MISC. PUBLICATION 200, U. S. DEPT. OF AGRICULTURE 



shaped, 3-nerved, subacute. Erect perennials with short creeping rhizomes, 

 narrow, firm, flat blades, the uppermost much reduced, and narrow panicles, 

 the slender branches ascending or appressed. Type species, Anthaenantia 

 villosa. Name from Greek anthos, flower, and enantios contrary. (Beauvois 

 misinterpreted the structure of the spikelet.) 



In pine barrens A. rufa may be an important element in the natural pasture. 



Blades erect or spreading, rather blunt or rounded at the apex, linear, folded at base; panicle 

 usually purple 1. A. rufa. 



Blades ascending or spreading (on the average shorter and broader than in A. rufa), tapering 

 to the apex, rounded at base; panicle usually pale 2. A. villosa. 



1. Anthaenantia rufa (Ell.) Schult. 

 (Fig. 821.) Culms slender, 60 to 120 

 cm. tall; blades elongate, 3 to 5 mm. 

 wide, often scabrous; panicle 8 to 15 

 cm. long, usually purple; spikelets 3 

 to 4 mm. long. % — Moist pine 

 barrens, Coastal Plain, North Caro- 

 lina to Florida and eastern Texas. 



2. Anthaenantia villosa (Michx.) 

 Beauv. (Fig. 822.) Differing from A. 

 rufa in the wider, mostly shorter, 

 spreading blades and in the usually 

 pale panicles. % — Dry pine bar- 

 rens, Coastal Plain, North Carolina 

 to Florida and Texas. 



Figure 821. — Anthaenantia rufa, X 1. (Amer. Gr. 

 Natl. Herb. 290, N. C.) 



128. TRICHACHNE Nees 



(Valota Adans., inadequately published) 



Spikelets lanceolate, in pairs, short-pediceled, in 2 rows along one side of a 

 slender rachis; first glume minute, glabrous; second glume and sterile lemma 

 about as long as the fruit, 3- to 5-nerved, copiously silky; fertile lemma carti- 

 laginous, lanceolate, acuminate, usually brown, the flat white Iryaline margins 

 broad. Perennials with slender erect or ascending racemes, approximate to 

 rather distant along a slender main axis, forming a white to brownish sillsy 

 panicle. Type species, Trichachne insularis. Name from Greek thrix (trich-), 

 hair, and achne, chaff, alluding to the silky spikelets. 



Trichachne insularis is not relished by cattle, hence the name sourgrass by 

 which it is called in the West Indies; T. calif ornica is a constituent of the 

 ranges of the Southwest, and furnishes fair forage. 



Fruit 4 mm. long; spikelets tawny- villous 1. T. insularis. 



Fruit 3 mm. or less long (rarely 3.5 mm.); spikelets white-villous. 



Spikelets long-silky, the hairs exceeding the spikelet; fruit 3 to 3.5 mm. long. 



Panicle branches stiffly ascending or spreading, comparatively few-flowered; fruit 



oblong-lanceolate, gradually pointed .— . 3. T. patens. 



Panicle branches appressed, densely flowered ; fruit obovate, abruptly pointed, the point 



scarcely indurate 2. T. californica. 



Spikelets short-silky, the hairs not exceeding the spikelet; fruit 2.4 mm. long. 



4. T. HITCHCOCKII. 



1. Trichachne insularis (L.) Nees. 

 Sourgrass. (Fig. 823.) Culms sub- base, 1 to 1.5 m. tall; leaves numer- 

 erect from a hard scaly hairy swollen ous; the sheaths sparsely hirsute; 



