114 



CONTRIBUTIOK-S FROM THE NATIONAL HEKBAETTJM. 



Panicum distichum lancifolium Griseb. Fl. Brit. W. Ind. 548. 1864. Grisebach bases 

 this upon a specimen from Trinidad collected by Crueger. The type, Crueger 84, 

 in the Grisebach Herbarium, is an exceptionally robust plant, with numerous racemes 

 and villous nodes. Grisebach states that the rachis of the branches is glabrous, but 

 the type has slender bristles thinly Interspersed. It resembles Hart's no. 732 from 

 Jamaica. 



DESCRIPTION. 



Plants annual, usually decumbent or creeping at base, rooting at the nodes and send- 

 ing up erect branches, smaller plants sometimes erect; culms usually branching, 25 

 to 100 cm. high, the nodes villous or sometimes glabrous or nearly so; sheaths elongated, 

 but usually less so than the internodes, keeled, separating more or less from the culm, 

 exposing the long prophyllum, and inrolled at the summit, somewhat simulating a 

 petiole to the blade, glabrous or sometimes ciliate or sparsely 

 hirsute; ligules wanting; blades ascending or spreading, narrowly 

 lanceolate, 4 to 20 cm. long, 7 to 15 mm. wide, broadest near the 

 cordate or truncate base, puberulent at the very base, otherwise 

 glabrous or sometimes sparsely pubescent; panicles consisting of 

 10 to 40 spike-like, densely-flowered, somewhat spreading racemes 

 along an axis 5 to 15 cm. long, the lower distant; racemes 1 to 3 cm. 

 long, straight or curved, bearing numerous spikelets in clusters of 

 1 to 3 secund on the lower side, the rachises copiously to sparsely 

 papillose-hispid, the hairs 1 to 3 mm. long, wanting in occasional 

 specimens; spikelets about 1.5 mm. long, 0.6 mm. wide, and nearly 1 mm. thick; first 

 glume about half the length of the spikelet; second glume and sterile lemma equal, 

 the former 5, the latter 3-nerved, both scabrous on the midnerve at the apex, the 

 sterile palea as long as its lemma, becoming subrigid and forcing open the spikelet; 

 fruit 1.3 mm. long, 0.6 mm. wide. 



This species differs from P. laxum in the more freely branching habit, compara- 

 tively shorter and uniformly cordate or truncate blades, and smaller panicles of shorter, 

 denser racemes, usually conspicuously bristly. In the following specimens the 

 bristles are wanting: Curtiss 305, Rovirosa 599, Rushy & Squires 79. The latter is also 

 exceptional in having pubescent spikelets. In this species an occasional intemode 

 is much shortened, thus giving a few leaves the appearance of being nearly in pairs. 

 Most of the specimens from North America have villous nodes, but those from South 

 America are commonly glabrous on the nodes. 



Fig. 108.— p. pilo- 

 sum. From type 

 specimen. 



DISTRIBUTION. 



Fields and open woods, Mexico, West Indies, and south to Brazil. 

 Mexico: Mirador, Liebmann 411; Chiapas, Nelson 3056; San Juan Bautista, 



Rovirosa 599. 

 Guatemala: Los Andes, Kellerman 5119; Dept. Alta Vera Paz, Goll 11, Tuerck- 



heim 8797. 

 Honduras: San Pedro Sula, Thieme 5587 in part; Bonacco Island, Gaumer. 

 Nicaragua: Wright. 

 Costa Rica: Rio Hondo, Cook & Doyle 499; Talamanca, Tonduz 9495; Puerto 



Viejo, Biolley 7463. 

 Panama: FendWiQ^. 

 Cuba: Hen'adura, Tracy 9063, Van Hermann 763; Dayaniguas, Wright 3451 in 



part; Sancti Spiritus, Leon 908; Isle of Pines, Curtiss 305, Taylor 36. 

 Jamaica: Gordon Town, Hart 732; Navy Island, Millspaugh 1859 (Hitchcock 



Herb.), Port Morant, Hitchcock in 1890 (Hitchcock Herb.). 

 Leeward Islands: Guadeloupe, Duss 41M. 

 Windward Islands: Granada, Broadway in 1904. 

 Colombia: Santa Marta, Smith 203. 





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