xv, 6 Merrill: Additions to Flora of Guam 541 
A glabrous, erect, apparently tufted perennial grass up to 60 
cm high. Leaves rather rigid, linear-lanceolate, 15 to 25 cm 
long, 5 to 8 mm wide, smooth, slenderly acuminate. Inflores- 
cence exserted, composed of about 15, ascending, somewhat 
crowded, racemosely arranged spikes 6 to 12 cm in length, the 
axis of the inflorescence up to 4 cm long. Axis of the spikes 
about 1 mm wide, the spikelets numerous, oblong to oblong- 
lanceolate, about 2.5 mm long, alternate, in two rows. First 
glume obsolete or reduced to an oblong-lanceolate, somewhat 
hyaline, pilose scale less than 1 mm in length. Second glume 
somewhat pubescent, 5- or 7-nerved, usually acute, the margins 
somewhat indexed over the flowering glume. Flowering glume 
lanceolate, glabrous, as long as the second empty glume. 
Guam, Cabras Island, Nelson 520 (type) April 24, 1919, near 
the seashore. The same species is represented by J. Guerrero 
U71, collected on rocks at Anaw Point, July 26, 1916. 
This species manifestly belongs in the small group of Poly- 
nesian ones discussed by Stapf following his description of 
Digitaria pacifica which includes D. pacifica Stapf, from Christ- 
mas Island; D. stenotaphrodes Stapf, which extends from the 
Caroline Islands to the Paumotu Archipelago; and D. platy- 
carpha Stapf, from Bonin Islands. These species, as Stapf has 
indicated, form a well-marked natural group which seems to 
be peculiar to the Pacific islands. To this group may also be 
added Digitaria mariannensis Merr., the type of which was also 
from Cabras Island, Guam, but which differs radically from the 
other species mentioned above in its entirely different habit; 
in its small size ; in its paired spikes ; and in being ciliate-pilose. 
The group is well characterized by its very greatly reduced or 
obsolete first glume, the spikelets generally consisting of a single 
empty glume with the flowering glume and its palea. Digitaria 
robinsonii is well characterized in the group by its numerous 
spikes. 
CYPERACEAE 
SCLERI A Linnaeus 
SCLERIA LITHOSPERMA (Linn.) Sw. Prodr. (1788) 18. 
Guam, Nasso River, Nelson 308, March 21, 1918, common 
along the banks of the river. A common pantropic species not 
previously recorded from Guam. 
168743 - 
