HITCHCOCK AND CHASE — NORTH AMERICAN GRASSES. 3 



1. Ichnanthus mayarensis (Wright) Hitchc. 



Panicum mayarense Wright, Anal. Acad. Cienc. Habana 8 : 296. 1871. " May- 

 an Aba jo," Cuba. The type specimen in the Gray Herbarium (Wright 3468) 

 consists of several culms with decumbent bases, sessile or nearly sessile blades 

 2 to 3 mm. wide, and a panicle one-fourth the entire height of the plant. 



Ichnanthus mayarensis Hitchc. Contr. U. S. Nat. Herb. 12: 229. 1909. Based 

 on Panicum mayarense Wright. 



Ichnanthus wrightii Hitchc. Contr. U. S. Nat. Herb. 12: 229. 1909. " Wright's 

 3880. U. S. National Herbarium no. 559959 of this collection is the type." This 

 was collected at Rio Seco in Arroyo Hondo, Pinar del Rio, Cuba. The specimen 

 consists of several delicate sterile culms rooting at the nodes, the thin blades 

 as much as 1 cm. wide with petioles as much as 12 mm. long, and of a few 

 culms, lacking the base, bearing small panicles. The plants appear to have 

 grown in the shade. 



DESCRIPTION. 



Culms slender, wiry, straggling or spreading, rooting at the lower nodes, 20 

 to 40 cm. long, glabrous or the lower part minutely pubescent, striate, the nodes 

 several; sheaths shorter (often much shorter) than the internodes, striate, 

 glabrous or sparsely papillose-hispid on the surface, puberulent on the margin, 

 especially toward the apex ; blades lanceolate to narrowly elliptic, 2 to 5 cm. 

 long, 3 to 6 mm. wide (or exceptionally as much as 1 cm. wide), striate, gla- 

 brous throughout or scaberulous above, abruptly narrowed at base into a petiole 

 1 to 5 mm. long, or on the sterile shoots as much as 15 mm. long ; panicles 2 to 

 10 cm. long, usually long-exserted, the few main branches as much as 3 cm. 

 long, rather stiffly spreading, the primary and secondary axes glabrous or 

 scaberulous ; spikelets about 3 mm. long, lanceolate, nearly terete, acute, gla- 

 brous, the unequal pedicels 0.5 to 2 mm. long; first glume 1.5 mm. long, broad 

 and clasping at base, acute ; second glume and sterile lemma equal, 3 mm. long, 

 acuminate, strongly nerved, the sterile palea narrow, about 1 mm. long ; fertile 

 lemma 2 mm. long, acute, only slightly compressed dorsally, the margins 

 inrolled, nearly or quite meeting, the scars at base about 0.5 mm. long, the 

 stipe obsolete. 



At the time Ichnanthus wrightii was described there were no specimens at 

 hand except those collected by Wright. The specimens received since then 

 show that the two forms must be united under one species. 



DISTRIBUTION. 



Dry pine woods and palm barrens, Cuba. 

 Cuba: Mayarl, Wright 3468. Arroyo Hondo, Wright 3880. Woodfred, Shafer 

 2966, 3058. Campo Florido, Ledn 3450, 4143. Madruga, Ledn 6373. 



Explanation of Plate 1. — Ichnanthus mayarensis. Specimen from Campo Florido, 

 Cuba, Le6n 4143 (U. S. Nat. Herb. no. 946900). Natural size. 



2. Ichnanthus tenuis (Presl) Hitchc. & Chase. 



Oplismenus tenuis Presl, Rel. Haenk. 1 : 319. 1830. " Hab. in Meixico, Pan- 

 ama." A duplicate type has been examined at the herbarium of the Petrograd 

 Botanical Garden. 



Panicum exile Steud. Syn. PI. Glum. 2: 45. 1854. Based upon Oplismenus 

 tenuis Presl, the name changed probably because of Panicum tcnue Roxb. 



