364 MISC. PUBLICATION 243, U.S. DEPT. OF AGRICULTURE 
wide; spikes 2 to 6 cm long, the burs not crowded; burs 3.5 to 5 mm 
wide (excluding the spines), somewhat tapering at the base, glabrous; 
spines spreading or refiexed, all glabrous and flat, broadened at the 
base, the lowest shorter, the upper 5 to 6 mm long; spikelets 2 or 3, 
5.5 to 7 mm long (fig. 335). ; 
Sandy open ground, Florida, Cuba, Jamaica, and Hispaniola. 
Cusa: Morilo, Ekman 17402. Isla de Pinos, Britton and Wilson 
14934. 
. JAMAICA: Southern Manchester, Harris 12690; Hitchcock 9851 (New 
orest). 
Harti: Tortuga Island, Ekman H 9760. 
FIGURE 335.—Cenchrus gracillimus. Bur, two views of spikelet, and floret, X 5 (type collection). 
Dominican Repusuic: Matanzas, Ekman H 15909. Punto Icacos, 
Ekman H. 15786. 
7. Cenchrus microcephalus Nash, Contrib. U. S. Natl. Herb. 18: 
356. 1917. Bahamas, Britton and Millspaugh 2249. 
Plants probably perennial, tufted, with numerous leafy sterile 
shoots at the base, glabrous as a whole; culms 30 to 70 cm tall, slender, 
scabrous below the spike, ascending 
from a decumbent base, branching 
from the middle and upper nodes; 
blades folded at base, often flat 
above, rather thin, 10 to 20 cm long, 
2 to 3 mm wide, pilose on the upper 
surface; spikes 3 to 5 cm long; burs 
(including the bristles) about 6 mm 
long and 5 mm wide, the body 
scarcely wider than the thick base; 
FIGURE 336.—Cenchrus ‘microcephalus. Bur spines flat, broadened at the base, 
two views of spikelet, and floret, X 5 (type). the lowest short and spreading, the 
upper stout, ciliate at base, shorter 
than the 5 or 6 lobes of the involucre, these erect or ascending, ciliate 
nearly to the summit, spikelets usually 2, 4 to 4.5 mm long (fig. 336). 
Known only from the Berry Islands. 
Bauamas: Berry Islands, Britton and Millspaugh 2211, 2249. 
