1916] Fernald & Weatherby,— Puccinellia 5 
In the following synopsis of the species of Puccinellia of eastern 
North America only those species which we know from south of 
Hudson Straits are included, but in the citation of specimens stations 
in western North America are often indicated, especially in the cases 
of newly described or newly interpreted species and varieties. The 
plates which have been most kindly prepared for us by Mr. R. E. 
Torrey illustrate details of all the species here included and some which 
have heretofore been ascribed to the region. 
Key To THE SpEcIES AND VARIETIES OF PUCCINELLIA IN EASTERN NorTH 
MERICA. 
A. Anther 1.5-2.2 mm. long. 
Flowering culms tall, 2-8 dm. high: branches of the panicle scabrous: 
lemmas 4-5 mm. long, pubescent on the nerves espe 
P. maritima 
Flowering culms low, 0.4-1 dm. high: branches of bg pent smooth: 
lemmas 2.8-3 mm. long, glabrous. ......... P. phryganodes. 
A. Anther 0.5-1 mm. long (1-1.2 mm. in P. ieciday. aes 
B. Grain 1.4-1.7 mm. lon 
C. Lower branches of the Gocinnrativels short panicle (0.2-1.6 dm. 
long) densely flowered nearly to the base or at least below the middle: 
lemmas thick and coriaceous, without a broad hyaline tip; the mid- 
nerve reaching the apex, often excurrent as a very short mucro. 
. P. fasciculata. 
C. Lower branches of the panicle floriferous chiefly above the middle, 
or, if much below, loosely flowered and the panicle much elongated 
(2-3 dm. long): lemmas thin and membranaceous in texture (firm in 
P. laurentiana and sometimes in P. paupercula), or at least with a 
broad hyaline tip; the midnerve not excurrent. 
Lemmas erose-ciliolate or serrulate under a lens. 
E. Glumes and lemmas truncate, erose-ciliolate under a lens. 
Mature panicle broadly ovoid, loose, its branches spreading 
or reflexed. 
Leaves of the culm 2-6 mm. wide, flat: panicle 0.8-2 dm. 
long: lemmas 2-2.5 mm. long........5. P. distans, 
Leaves of the culm 2 mm. wide or lees; becoming more or 
less i involute: panicle 4—9 cm. long: lemmas 1.5-2 mm. 
long. .(5.) P. distans, var. tenuis. 
Mature paniele. slender-ylindre to ee dense, its 
branches erect or ascending. .6. P. coarctata. 
E. Glumes and lemmas tapering to an aot or obtusish tip, not 
truncate, erose-serrulate: panicle-branches erect or ascend- 
ing, rarely spreading. 
