HITCHCOCK — REVISIONS OF NORTH AMERICAN GRASSES. 119 



Jamaica: Cinchona, Amer. Gr. Nat. Herb. 420; Harris 11316, 11333, 11417, 11432, 12480. 



Abbey Green, Hitchcock 9362; Harris 11585. Catherines Peak, Hitchcock 9732. 



Clyde River, Harris 11445. Cold Spring Gap, Harris 11336, 12489. Hardware 



Gap, Harris 11543. Sir Johns Peak, Harris 11595. 

 Colombia: Santa Marta, Smith 207. 

 Venezuela: Without locality, Fendler 1637, 2504. 



Explanation of Plate 29. — Isachne rigens. Specimen from Jamaica, Harris 12489. Natural size. 



6. Isachne angustifolia Nash. 



Isachne angustifolia Nash, Bull. Torrey Club 30: 377. 1903. "On the summit of 

 El Yunque, Luquillo Mountains, Porto Rico, Wilson no. 160." The type, in the New 

 York Botanical Garden Herbarium, is a long branched shoot with numerous leaves 

 and several panicles. 



DESCRIPTION. 



Culms clambering, as much as 2 meters long and 2 mm. thick, hard and wiry, 

 with a long naked base, branching from the upper nodes, the branches long, leafy, 

 nearly parallel, bearing secondary branches toward the ends, the whole forming a 

 wide, flabellate or loosely corymbose mass, in its most characteristic development 

 pushing through the jungle of stream bank or trail side and hanging over bushes; 

 sheaths appressed papillose-pilose or roughened with papillae, or glabrous, the margin 

 ciliate; ligule a ring of very short stiff hairs less than 0.5 mm. long; blades narrowly 

 lanceolate, 3 to 15 cm. long, but mostly more than 5 cm. long, 5 to 12 mm. wide 

 rather firm and stiffly spreading, scaberulous or glabrate, papillose-ciliate at base or 

 papillose only; panicles ellipsoid or oblong, as much as 15 cm. long, the branches 

 stiffly ascending or finally spreading, the branchlets and pedicels finally divaricate, 

 these and the main axis scabrous; spikelets about 1.5 mm. long; glumes minutely 

 hispidulous toward the tip ; florets and rachilla glabrous. 



DISTRIBUTION. 



Rocky slopes among brush, Porto Rico (at higher altitudes) and Guadeloupe. 



Porto Rico: Utuado, Sintenis 6421. Rio Icaco, Shafer 3477. Adjuntas, Sintenis 

 4045. El Yunque, Sintenis 1355. Maricao, Chase 6222; Britton & Cowell 4271. 

 Sierra Luquillo, Hioram 369. Gayey, Chase 6750. Monte Alegrillo, Britton, 

 Stevens & Hess 2566. Monte Torrecilla, Britton, Cowell & Brown 5595. 



Leeward Islands: Guadeloupe, Dnss 2705. 



Explanation of Plate 30.— Isachne angustifolia. Specimens from Porto Rico, Chase 6222 and 6750. 

 Natural size. 



7. Isachne arundinacea (Swartz) Griseb. 



Panicum arundinaceum Swartz, Prodr. Veg. Ind. Occ. 24. 1788. "Jamaica." The 

 type, in the Swartz Herbarium at Stockholm, consists of two shoots, one with a young 

 unexpanded panicle, the other with a spreading panicle past maturity. The glumes 

 of the former are hispid at the summit, of the latter glabrous. 



Panicum glaucescens H. B. K. Nov. Gen. & Sp. 1: 104. 1816. "Crescit locisplanis, 

 propatulis Novae Andalusiae juxta Bordones et in excelsis, opacatis Andium prope 

 Pasto." The type, in the Paris Herbarium, "in excelsis prope Pasto," is a shoot with 

 everal leaves and a small, rather dense panicle. 



Isachne panicea Trin. Gram. Pan. 253. 1826. Trinius unites Panicum arundinaceum 

 and P. dispermum, giving both names as synonyms, but his description applies better 

 to the first ("Panicula densiuscula"). 



Isachne arundinacM Griseb. Fl. Brit. W. Ind. 553. 1864. Based on Panicum 

 arundinaceum Swartz. 



