90 A FLORA OF MANILA 
3. Empty glumes usually muricate, the second and third cuspidate or 
awned., 
4. Lower spikes as long as or shorter than the internodes; third 
glume awnless or nearly so; spikelets 2.5 to 3 mm long. 
4. P. colonum 
4. Lower spikes much longer than the internodes; coarse erect 
grasses, the spikelets usually long-awned. 
5. Spikelets nearly 5 mm long, green or purplish; an aquatic 
ayy MARS SSR UB eS SALA CA a ha ei 5. P. stagninum 
5. Spikelets 3.5 to 4 mm long, usually purplish........ 6. P. crusgalli 
2. Spikelets crowded in spiciform or narrow, cylindric panicles, or pedi- 
cellate on the spreading, racemosely arranged panicle-branches. 
3. Branches elongated, ascending or spreading................ 7. P. auritum 
3. Panicles dense, cylindric. 
4, Spikelets about 5 mm long, acuminate; a coarse, perennial, 
ngwatic PTASH oyster eee ee 8. P. amplexicaule 
4. Spikelets about 2.5 mm long; a slender, erect annual grass. 
. 9. P. indicum 
2. Spikelets in open, diffuse panicles. 
3. First glume as long as the spikelet or nearly so; spikelets promi- 
nently acuminate. 2.2... 2) Se See 10. P. caudiglume 
3. First glume much shorter than the spikelet. 
4. Second glume decidedly shorter than the flowering glume; panicles 
ees 1 (RR OP Dae eR SS ek AR cn bts 11. P. nodosum 
4. Second glume equaling or longer than the flowering glume; pani- 
cles decompound. 
Sr 1 1 ORR Mie eal ro pp ene ie sea ae et 12. P. psilopodium 
5. Perennial. 
6. Tall, leafy, 2 to 3 m high; cultivated.............. 13. P. maximum 
6. Less than 2 m high. 
7. Panicle branches rather stiff, spreading; spikelets 3.5 to 4 
mm long, aquatic or subaquatic................ 14. P. paludosum 
7. Panicle branches somewhat nodding; spikelets 3 mm long. 
15. P. repens 
1. Spikelets laterally compressed; small, slender, more or less prostrate, 
spreading grasses. 
2. Panicles very lax, open, the spikelets scattered............ 16. P. warburgti 
2. Spikelets densely crowded on the usually ascending branches. 
17. P. pilipes 
1. P. FLAVIDUM Retz. 
A loosely tufted, erect, somewhat branched, rather coarse grass 0.5 
to 1 m high, the stems somewhat compressed. Leaves linear-lanceolate, 
smooth, glabrous, acute or acuminate, 8 to 15 cm long, 5 to 10 mm wide, 
the lower sheaths usually loose. Inflorescence elongated, of erect, stout, 
scattered, racemosely arranged spikes shorter than the internodes, the 
spikes 1 to 2.5 cm long, about 5 mm wide. Spikelets very pale, densely 
arranged in 2 rows, divaricate, about 3 mm long. 
Very common in open waste places, roadsides, etc., fl. all the year; 
throughout the Philippines at low altitudes, certainly introduced. Trop- 
ical Asia and Africa, Malaya. ‘ 
2. P. punctatum Burm. 
A stout, erect, perennial grass 1 to 1.5 m high, the base usually floating 
