288 MISC. PUBLICATION 243, U.S. DEPT. OF AGRICULTURE 
axis with viscid spots; spikelets nearly spherical, about 1.7 mm long, 
puberulent. Autumnal phase prostrate-spreading, rather sparingly 
branching (fig. 270). 
Sandy soil and gravelly banks at low and medium altitudes, eastern 
United States and Mexico to Ven- 
ezuela; Cuba. 
Cusa: Isla de Pinos, Ekman 
11820. 
79. Panicum erectifolium Nash, 
Bull. Torrey Bole Club 23: 
148. 1896. ased on P. 
aes var. florida- 
num Vasey. 
Panicum sphaerocarpon var. 
floridanum Vasey, U. S. Dept. 
Agr., Div. Bot. Bull. 8: 33. 1889. 
eee floridanum Trin., 1834. 
orida. 
Panicum floridanum Chapm., 
Fl. South. U.S. ed. 3. 585. 1897. 
Vernal culms erect or ascend- 
ing usually stout, glabrous, 30 to 
70 ceils vee sabe e. 
cep e ciliate margin; ligule 
atic 0.3 os long; blades thick, 
m, ascending or erect, 7 to 13 
FIGURE 270.—Panicum sphaerocarpon. Plant, X 1 Oat long, fie ee wide, the 
two views of spikelet, and floret, X 10 (Deam). a vier ee ones Ueamed much 
onger than the others, tapering 
from the cordate base to the acuminate apex, smooth on both surfaces, 
ciliate toward the base; panicles 6 to 12 cm long, half as wide, densely 
flowered; spikelets about 1 mm long, subspherical, densely puberulent. 
Autumnal phase remaining erect and simple, 
finally producing a few erect branches (fig. 271). 
Moist pine barrens, swamps, and borders of 
ponds, southeastern United States; Cuba. 
Cusa: Remates, Ekman 11188. Vuelto abajo, 
Wright 3462. Laguna del Bufeo, Shafer 11021. he ee 
Laguna Santa Maria, Britton and Gager 7170. ~ ifolium. Two views of 
Motembo, Léon 8615. Isla de Pinos, Brittonand —Pikelet, andi floret, X 10 
Wilson 14150, 14705, 15706. : 
80. Panicum albomarginatum Nash, Bull. Torrey 
Bot. Club 24: 40. 1897. Florida. 
Vernal phase usually grayish green, often pur- 
plish; culms densely tufted, slender but firm, 
ascending or spreading, glabrous, 15 to 40 cm | 
tall; leaves crowded at the base, distant above; revre 272—Panieum"albo- 
blades thick and firm, those of the midculm 4 to JUzgium. a iforet. 10 
6 cm long, 4 to 6 mm wide, glabrous, the margin (type). 
(when dry) prominent, white, cartilaginous, the 
crowded basal blades as much as 11 cm long, the uppermost usually 
much reduced; panicles 3 to 6 cm long; spikelets about 1.5'mm long, 
pubescent. Autumnal phase spreading, the primary culms branching 
from the base and lower nodes, forming bushy tufts (fig. 272). 
