HITCHCOCK AND CHASE — NORTH AMERICAN GRASSES. 9 



long; first glume 2 mm. long, broad and clasping at base, acute; second glume 

 and sterile lemma nearly equal, clasping at base, acuminate, the sterile palea 

 small and narrow, about 1 mm. long; fertile lemma nearly 3 mm. long, acute, 

 the margins flat and overlapping toward the apex, inrolled and nearly meet- 

 ing toward the base, the scar at base very short, extending downward into a 

 minute wing on the very short stipe. 



DISTRIBUTION. 



Forests and old fields ; known only from Yucatan peninsula. 

 Yucatan : Izamal, Gaumer 854. Tiap, Linden. 

 Quintana Roo: Buena Vista Xbac, Gaumer 1111. Chichankanab, Gaumer 2181. 



Explanation of Plate 6. — Ichnanthus lanceolatus. Type specimen. Natural size. 

 7. Ichnanthus nemoralis (Schrad. ) Hitchc. & Chase. 



Panicum nemorale Schrad.; Schult. Mant. 2: 255. 1824. "In Brasilia, Prin- 

 ceps Sereniss. Maximil. Neowidensis." The type has not been examined but 

 the description identifies the species. 



Panicum martianum Nees. Agrost. Bras. 138. 1829. " Habitat ad Almadam 

 [Brazil 1 (Mart.)." Nees describes three varieties of which the first, a, is the 

 type. This is described as having the sheaths, except the margins, glabrous. 



Panicum petiolatum Nees, Agrost. Bras. 140. 1829. " Habitat in udis ad 

 Guaratingueta, in vicinia Paraibae fluminis, provinciae S. Pauli," Brazil. The 

 type specimen, collected by Martius, was examined in the Munich Herbarium. 



Ichnanthus petiolatus Doell in Mart. Fl. Bras. 2 2 : 278. 1877. Based on Pani- 

 cum petiolatum Nees. 



Ichnanthus martianus Doell in Mart. Fl. Bras. 2 2 : 280. 1877. Based on Pani- 

 cum martianum a Nees. 



Ichnanthus nemoralis Hitchc. & Chase, Contr. U. S. Nat. Herb. 18: 334. 1917. 

 Based on Panicum nemorale Schrad. 



description. 



Culms as much as 1 meter tall, more or less decumbent at base, pubescent or 

 glabrous ; sheaths more or less pubescent, villous on the collar ; ligule a ciliate 

 membrane about 1 mm. long ; blades elliptic or narrowly lanceolate, up to 

 about 10 or 15 cm. long, as much as 3 cm. wide, narrowed into a petiole 

 1 to 2 mm. long, many-nerved, pubescent on both surfaces or glabrous 

 above ; panicle 10 to 15 cm. long, the few stout branches stiffly ascending, pubes- 

 cent at base; spikelets about 4.5 mm. long, glabrous, or the glumes slightly 

 roughened on the internerves toward the apex ; fruit 3.5 mm. long, the append- 

 ages 1.5 mm. long. 



DISTRIBUTION. 



Among shrubs, Trinidad to Brazil. 

 Trinidad: Bot. Gard. Herb. 2278. 

 Tobago: Broadway, 4472. 



Venezuela : Island of Margarita, Johnston 208. 

 Brazil: Toca de Onca, Rose 2Q9T7 ; Riedel 1193, 1194A. Rio Janeiro, Wilkes 



Expl. Exped. 14 ; Mertens. State of Parana, Duse'n 7594. Without locality, 



Salzmann. 



Explanation of Plate 7. — Ichnanthus nemoralis. Specimen from Tobago, Broadway 

 4472 (U. S. Nat. Herb. no. 725595). Natural size. 



115803—20 2 



