HITCHCOCK AND CHASE — NORTH AMERICAN PANICUM. 39 



Panicum fasciculatum genuinum Doell in Mart. Fl. Bras. 2 2 : 204. 1877. Based on 

 P . fasciculatum Swartz . 



Panicum fasciculatum flavescens Doell in Mart. Fl. Bras. 2 2 : 205. 1877. Based on 

 P. flavescens Swartz. 



Panicum fasciculatum fuscum Doell in Mart. Fl. Bras. 2 2 : 205. 1877. Based on P. 

 fuscum Swartz. 



Panicum fasciculatum was described under a phrase name and figured by Sloane, a 

 whose type is at the British Museum of Natural History. & Kuntze misapplies the 

 name Panicum paniculatum (L.) Kuntze, c based on Paspalum paniculatum L., to this 

 species, owing to the fact that Linnaeus erroneously cites Sloane's plate of Panicum 

 fasciculatum after his description of Paspalum paniculatum, the type of which is in the 

 Linnsean Herbarium. ^ Nash« also later made the combination Panicum paniculatum 

 on the same grounds. 



DESCRIPTION. 



Plants erect or spreading from a decumbent base, the more robust becoming much 

 branched from the lower nodes; culms 30 to 100 cm. or more high, glabrous or scabrous, 

 or sometimes pubescent below the panicle or hispid below the appressed-pubescent 

 nodes; sheaths sometimes shorter, sometimes longer than the internodes, glabrous or 

 more or less papillose-hispid, densely ciliate, pubescent at the juncture with the 

 blades; ligule a dense ring of hairs about 1 mm. long; blades flat, 4 to 30 cm. long, 6 

 to 20 mm. wide, glabrous, usually scabrous above, sometimes sparsely hispid on one 

 or both surfaces, the nerves in the larger blades conspicuous, sometimes appearing 

 somewhat plicate; inflorescence short-exserted or included at base until maturity, 

 consisting of a series of spike-like racemes arranged along a scabrous, sometimes pilose, 

 main axis, 5 to 15 cm. long, the racemes 5 to 10 cm. long, solitary or fascicled, narrowly 

 ascending to somewhat spreading, spikelet-bearing from the base, or naked below, 

 the short-pediceled spikelets approximate or somewhat crowded, borne singly, or two 

 or three together on short branchlets, along the under side of the axis; spikelets 

 bronze to mahogany colored, 2.1 to 2.5 mm. long, in occasional specimens as much as 

 3 mm. long, obovate, turgid, abruptly short-pointed, glabrous; first glume clasping, 

 about one-third the length of the spikelet, subacute, 5 to 7-nerved; second glume and 

 sterile lemma slightly exceeding the fruit, 9-nerved, faintly to strongly transversely 

 wrinkled between the nerves; fruit 1.9 to 2.3 mm. long, obovate, obscurely apiculate. 



This species is variable in the amount of pubescence and in the size of the spikelets. 

 Almost all the West Indian specimens cited below have spikelets not over 2.3 mm. 

 long. The greater number of specimens from Mexico and the United States have 

 spikelets 2.5 to 2.8 mm. long, while about half the Central American specimens have 

 the larger spikelets. This difference in size can not be correlated with any other 

 character. 



DISTRIBUTION . 



Moist open ground, often a weed in fields and along roadsides, southern Florida and 

 Texas, southward through Mexico and the West Indies to Brazil and Ecuador. 



Florida: Cape Canaveral, Curtiss 3589 ; Lastero Bay, Garber 36; Sneeds Island, 

 Tracy 6455; Caxambas Island, Simpson 275; Marco, Hitchcock Lee Co. 

 PI. 484; Key West, Rugel; without locality, Blodgett. 



a Voy. Jam. 1 : 115. pi. 72. f. 2. 1707. 



b See Hitchcock, Contr. Nat. Herb. 12: 131. 1908, for an account of Sloane's Ja- 

 maica grasses. 

 ' c Rev. Gen. PI. 3 : 363. 1898. 



d See Hitchcock, Contr. Nat. Herb. 12 : 116. 1908. 



e Bull. Torrey Club 30: 381. 1903. 



