Part 1, 1909] POACEAE 87 
back with about five longitudinal rows of broadly oblong pits; pedicellate spikelet a little 
smaller than the sessile one, perfect, the first scale without pits, the pedicel linear-clavate, 
winged on one side, the wing extending into a tooth equaling one half the width of the 
pedicel at its apex. 
TYPE LOCALITY : Rio Blanco, Mexico. 
DISTRIBUTION : Mexico and (according to Fournier) adjacent United States. 
7. HEMARTHRIA R. Br. Prodr. 207. 1810. 
Perennial, usually decumbent or ascending grasses, with extravaginal innovations, flat 
leaf-blades which are conduplicate in vernation, and compressed racemes or spikes borne 
singly at the apex of the stem and its branches. Rachis of the racemes or spikes tardily 
disarticulating, the apex of the separated internodes flat and not furnished with a pit or 
excavation, the pedicel usually grown to the rachis. Spikelets 1-flowered, dorsally com- 
pressed ; first scale of the sessile spikelet coriaceous, flat on the back, with the margins very 
narrowly inflexed; second scale membranous, somewhat keeled, often adnate to the 
rachis; third scale hyaline, empty; fourth scale almost nerveless, enclosing a perfect flower 
and also usually a palet. Stamens 3. Stigmas twice as long as the styles, exserted above 
the base of the spikelet. 
Type species, Rottboellia compressa L. 
1. Hemarthria fasciculata (Lam.) Kunth, Rev. Gram. 453. 1831. 
Rottboellia fasciculata Lam. Tab. Encye. 1: 204. 1791. 
Stems up to 8 dm. tall, compressed; leaf-sheaths compressed, keeled, glabrous, ex- 
cepting on the ciliate margin; blades up to 2 dm. long and 6 mm. wide; spikes 3-8 cm. 
long, 3-4 mm. wide, compressed ; sessile spikelets 5-7 mm. long, oblong, the first scale 
constricted below the obtuse apex ; pedicellate spikelets 5-6 mm. long, acute. 
TYPE LOCALITY: Barbary. 
DISTRIBUTION: Southwestern Texas, Mexico, and in warm temperate and tropical regions. 
ILLUSTRATIONS: Mart. Fl. Bras. 28: #/. 72, f.2; Bull. U. S. Dep. Agr. Agrost.7: (5; Beal, 
Grasses N. Am. 2:f.9. 
8. HACKELOCHLOA Kuntze, Rev. Gen. 776. 1891. 
Manisuris Sw. Prodr. 25. 1788. Not Manisurisl. 1771. 
Annual grasses with branching stems, flat leaf-blades and terminal and axillary short 
spikes which are sometimes partially included in the sheaths. Spikelets in pairs in exca- 
vations at the nodes of the rachis, one sessile, 1-flowered, the other pedicellate, but appear- 
ing as if sessile on account of the pedicel being adnate to the rachis, making its spikelet 
appear to form a pair with the sessile spikelet of the next higher internode. Scales of the 
sessile spikelet 4, awnless; first or outermost scale empty, firm, globose, pitted, covering 
the excavation in the rachis ; second scale oval-oblong, concave, thin, 1-nerved; third scale 
shorter than the second, empty ; fourth scale thin, hyaline, enclosing a perfect flower, and 
sometimes also a minute palet. Stamens 3. Styles distinct. Stigmas plumose. Pedicel- 
late spikelet differing much in shape from the sessile and equaling or exceeding itin length, 
ovate ; first scale 5-7-nerved, one margin narrowly infolded ; second scale equaling the first, 
keeled, the keels ciliate, 5-7-nerved; third scale shorter than the first, 2-nerved, rarely 
with a staminate flower; fourth scale nerveless or 1-nerved, sometimes with a staminate 
flower. 
Type species, Cenchrus granularis L. 
1. Hackelochloa granularis (1,.) Kuntze, Rev. Gen. 776. 1891. 
Cenchrus granularis I,. Mant. 575. 1771. 
Manisuris granularis Sw. Prodr. 25. 1788. 
Manisuris polystachya Beauv. Fl. Oware 1: 24. 1805. 
Tripsacum granulare Rasp. Ann. Sci. Nat. 5: 306. 1825. 
Stems 2-10 dim. tall, finally much-branched ; leaf-sheaths papillose-hirsute ; blades 1.5 
dm. Jong or less, 3-15 mm. wide, papillose-hirsute on both surfaces, ciliate on the margins ; 
