78 A FLORA OP MANILA 



erect, 15 to 30 cm long, the branches slender, spreading, whorled, fragile, 

 the joints clothed with long, soft, white hairs. Spikelets about 3.5 mm 

 long, very much shorter than the copious long white hairs at the base. 



In open waste places, fallow lands, etc., fl. Sept.-Nov., and Apr .-June; 

 very common and widely distributed in the Philippines. Southern Europe 

 through the tropics of the Old World to Australia. 



* 2. S..OFFICINARUM L. Tuba (Tag.); Caiia dulce (Sp.); Sugar Cane. 



A coarse, erect grass 1.5 to 3.4 m high, the stems green, yellow, or 

 purplish, 2 to 5 cm thick, the internodes long or short. Leaves yery large, 

 broad. Panicles very large, 40 to 80 cm long, white, the branches up to 

 35 cm in length, the stems glabrous below the panicle. Spikelets very nu- 

 merous, about 3 mm long, the surrounding white, villous hairs alsout twice 

 as long as the spikelet. (Fl. Filip. pi. 18.) 



Cultivated to a- small' extent in the vicinity of Manila, occasionally 

 flowering; extensively cultivated in the Philippines. Probably a native of 

 tropical Asia, now cultivated in all tropical countries; of prehistoric in- 

 troduction in the Philippines. 



10. ROTTBOELLIA Linnaeus ftlius 



Coarse, erect, annual or prennial grasses, the leaves mostly broad. 

 Spikes few or many, cylindric, solitary or panicled, the rachis fragile, the 

 joints usually excavated at the tip. Spikelets in pairs, 1 sessile and 1 

 pedicelled, the former perfect, the latter imperfect, its pedicel often adnate 

 to the joint, the spikelets more or less immersed in the hollowed outside of 

 the rachis-joints. Sessile spikelets with 4 glumes, the first coriaceous, 

 covering the excavation in the rachis-joint, the second thinner, keeled, the 

 third and fourth hyaline, not awned. (In honor of C. F. Rottboell, a Danish 

 botanist.) 



Species about 30, in the tropics of both hemispheres, 3 in the Philippines, 

 a single one in our area. 



1. R. exaltata L. f. Aguingay (Tag.). 



A coarse, erect, usually branched, annual grass 1 to 2.5 m high, the 

 stems stout, spongy inside, the sheaths armed with few or many, stiff, 

 irritating hairs. Leaves flat, 20 to 60 cm long, 1 to 3 cm wide, acuminate. 

 Spikes cyiin'dric, 8 to 15 cm long, about 3 mm in diameter, mostly solitary, 

 narrowed upward, readily breaking up, the joints 6 to 7 mm long. Spike- 

 lets immersed in the side of the rachis, the first glume of the second one 

 about 4 mm long, very coriaceous. 



In open, well-drained grass lands, thickets, etc., fl. all the year ; through- 

 out the Philippines. T.ropical Africa and Asia through Malaya to Australia. 



11. MANISURIS Swartz 



A slender, much-branched, annual grass, more or less haiiy, the leaves 

 cordate at the base. Spikes cylindric, slender, solitary, ajfillary and 

 terminal, numerous, the peduncles often confluent and forming a 

 leafy panicle, the rachis fragile, joints very short, deeply excavated. 

 Spikelets 1- or 2-flowered, in pairs, one sessile, globose, pitted externally, 

 the other pedicelled, ovate, flat, male. or neuter, its pedicel adnate to the 

 rachis-joint. Sessile spikelet with 4 glumes, the first globose, pitted, 

 awnless. (Said to be from the Greek "lizard" and "tail," in allusion to the 

 form of the spike.) 



A monotypic genus. 



