HITCHCOCK AND CHASE — NORTH AMERICAN GRASSES. 25 



with a ring of hairs at the summit or at least a tuft of hairs on either side, 

 sometimes pubescent on the margins toward the summit; ligule about 0.5 mm. 

 long, thin-membranaceous ; blades on vigorous shoots as much as 14 cm. long 

 and 2.5 cm. wide, but mostly about 8 to 12 cm. long and 1.5 to 2 cm. wide, 

 acuminate, rounded-tapering to the base, usually somewhat asymmetric, gla- 

 brous, scabrous on the margin and somewhat so on both surfaces ; panicles num- 

 erous, short-exserted, mostly 12 to 20 cm. long, nearly as wide, the slender 

 axis and distant spreading flexuous branchlets angled, scabrous, the pedicels 

 flexuous, spreading; spikelets pale, blotched with dark blue or purple at ma- 

 turity, 3.4 to 3.8 mm. long, globose-obovoid, the glumes and sterile lemma lanate- 

 ciliate toward the apex; fruit 3 mm. long, 2 mm. wide. 



In habit and general appearance L. patentiflora resembles L. sloanei, from 

 which it differs in the narrower average width of the blades and the more 

 loosely flowered, rather large panicles with smaller spikelets on flexuous spread- 

 ing pedicels. 



DISTRIBUTION. 



Borders of woods and jungles, Guatemala to Trinidad and Venezuela; also in 

 Dominica and Paraguay. 

 Guatemala: Cubilquitz, Tilrckheim 8782. 

 Salvador: San Salvador, Hitchcock 8962. 

 Nicaragua : Jinotepe, Hitchcock 8695. 

 Costa Rica : Rio CaHas, Jime'nes 720. 

 Leeward Islands : Dominica, Ramage in 1889. 

 Trinidad : Port of Spain, Hitchcock 10034, 10037, 10323, 10324 ; Amer. Gr. Nat. 



Herb. 592. 

 Tobago : Broadway 4841 ; Hitchcock 10255, 10257, 10268, 10270. 

 Venezuela: Carayaca, Jahn 303 in part. 

 British Guiana : Upper Demerara River, Jenman 4089. 

 Paraguay: River Pilcomayo, Rojas 292. 



Explanation op Plate 21. — Lasiacis patentiflora. Specimen from Tobago, HitcJicock 

 10268, type collection (U. S. Nat. Herb. no. 975660). Natural size. 



13. Lasiacis sorghoidea (Desv.) Hitchc. & Chase. 



Panicum lanatum Swartz, Prodr. Veg. Ind. Occ. 24. 1788. Not P. lanatum 

 Rottb. 1776. " Jamaica." The type specimen, marked " Jamaica, Swartz," has 

 been examined in the Swartz Herbarium at Stockholm. 



Panicum sorghoideum Desv. ; Hamilt. Prodr. PI. Ind Occ- 10. 1825. " Porto 

 Rico." The type specimen in the Paris Herbarium is laneiea with some uncer- 

 tainty as to locality, " America aequinox., Hispaniola." The note, " Je ne vois 

 pas en quoi ce Panicum differe du P. glutinosum," shows a close connection 

 with the note under the original description. "Habitu P. latifolio afflne, ab illo 

 autem aeque ac P. glutinoso distinctum." 



Panicum orinocense Willd. ; Spreng. Syst. Veg. 1 : 316. 1825, as synonym under 

 P. glutinosum Lam. The type, received from Humboldt, is in the Willdenow 

 Herbarium. 



Panicum praegnans Steud. Syn. PI. Glum. 1: 74. 1854. "P. fruticosum 

 Salzm. Oaxaca. Bahia." The fragmentary Oaxaca specimen, collected by 

 Buchinger, is in the Steudel Herbarium at Paris. This appears to be Lasiacis 

 sorghoidea. Salzmann's Bahia collection, labeled P. fruticosum, is Lasiacis 

 ligulata. Steudel's description is not sufficient to distinguish between the two 

 115803—20 3 



