14 Rhodora : [JANUARY 
conglomerate limestone and calcareous sandstone cliffs and ledges, 
Cow Head, July 23, 1910, Fernald & Wiegand, no. 2,615a. QUEBEC: 
rocky shore, Pointe Jones, Brest, Saguenay County, July 29, 1915, 
St. John, herb. Geol. Surv. Can.; rocky bank, Romaine, Lagorden- 
diére, Saguenay County, July 7, 1915, St. John, herb. Geol. Surv. 
Can. 
Superficially resembling the Greenland P. vaginata (Lange), n. 
comb.= Glyceria vaginata Lange, Fl. Dan. t. 2583 (1858); but differ- 
ing in its shorter spike (in P. vaginata 5-6-flowered), shorter nearly 
glabrous lemmas, which in P. vaginata are 3 mm. long and distinctly 
appressed-pubescent along the lower half of the nerves, and in the 
shorter and broader-tipped palea. 
= = Lemmas narrowed to an acute or obtuse tip, not truncate, ap- 
pressed-pubescent on the nerves below. 
° Plant whitish-green: panicle-branches smooth or nearly so: lemmas 
firm. 
. P.laurentiana,n. sp. Fias. 33-38. Laxe caespitosa perennis 
1-3 dm. alta rigida glauca; foliorum caulinorum laminis 3-6 cm. longis 
involutis, vaginis basilaribus albo-brunneis; ligula 1.5 mm. longa 
acutiuscula; panicula 0.6-1.3 dm. longa, ramis rigidis glabriusculis 
adscendentibus deinde divergentibus vix deflexis; spiculis 4-6.5 mm. 
longis 3-5-floris albescentibus; gluma inferiore 1-2 mm. longa an- 
lemmas ovate, hyaline above, 2.3-2.8 mm. long, abruptly acuminate, 
erose-ciliolate, very pubescent on the nerves below; the midnerv 
often finely scabrous toward the apex: palea a little shorter, lanceo- 
late, bidentate at the broad apex, scabrous above, ciliate at base: 
anthers 0.7-0.9 mm. long: grain 1.5-1.8 mm. long.— Coasts of Bona- 
