STUDIES OX AMEEICAN GEASSES. 



I. NEW OR LITTLE KNOWN GRASSES. 



By F. Lamson-Scribxer. 



In the investigations being carried on necessary to tlie preparation 

 of tlie proposed "Hajidbook of North American Grasses," new species 

 or species heretofore unidentified or incorrectly determined are met 

 with in the collections of the iSTational Herbarium or in those submitted 

 for examination. As the early publication of such new species and 

 revised determinations is desirable, it has been decided to publish such 

 matter and other investigations of purely technical character involving 

 original research as soon as sufficient material has accumulated to war- 

 rant such publication, and for such bulletins to continue the title of 

 "Stidies on American Grasses." 



In the present bulletin are included descriptions and illustrations of 

 a number of new or little known species of grasses, including two from 

 Mexico, collected during the past season, one by Dr. Edward Palmer, 

 which is probably new, and one by Mr. C. G. Priugle; and an exhaustive 

 study of the histological characters presented by the leaves of those 

 remarkable grasses, Jouvea pilosa and Jouvea straminca, and of the 

 peculiar and very well marked species of Eragrostis which is here 

 described under the name of \E. obtu.nfora, upon the supposition that 

 it is the same as the Brizopyrum ohtusijiorum of Fournier. 



Poa turner! Scribn. sp. nov. (Plate I). A stoloniferous and apparently dinccious 

 grass, 4 to 7 dm. liigli, with soft, flat leaves, and more or less sjjreading and 

 nodding panicles of rather large, compressed, 3- to 6-flowered spikelets. Culms 

 smooth, more or less geniculate at the lower nodes; nodes dark olive-green or 

 nearly black; sheaths striate, smooth; leaf blade 10 to 15 cm. hmg, 5 to 6 mm. 

 wide, acute, .scabrous near the apex, and sometimes .sparingly pilose on the 

 upper surface near the base, otherwise smooth; ligule hyaline, 5 to t! mm. long, 

 rounded at the apex. Panicle 8 to 15 cm. long, the slender bramhesiu threes or 

 fives (raiely in twosj, flower-bearing above the middle, naked below, the longer 

 lower ones 5 to 10 cm. long. Spikelets about 7 mm. long, ovate, 3- to 6 flowered, 

 glumes lanceolate, acuminate, the outer ones subequal, very acute, scarious 

 on the margins, 3-nerved, about e(iualing the nearest flowering glumes; flower- 

 ing glumes 5-nerved, scabrous on the keel near the acute apex, densely pilose 

 on the keel and marginal nerves below, with a copious tuft of long, cobwebby 

 hairs at the base, scabrous between the nerves above, more or less pubescent 

 between the nerves below in the fertile spikelets, margins scarious; palea a 

 little shorter than the glume, ciliate on the keel, and in the fertile spikelets 



pubescent between the nerves. 



5 



