HITCHCOCK—MEXICAN GRASSES. 875 
9. Poa albescens sp. nov. 
Perennial, the whole plant whitish; culms erect, cespitose, 20 to 30 cm. high, 
slightly scabrous below the panicle; sheaths glabrous, longer than the internodes, the 
old basal ones persistent, numerous, papery; ligule very short, the uppermost about 
1 mm., those of the innovations scarcely 0.5 mm. long; blades mostly basal and on 
the innovations, firm, folded, glabrous beneath, scabrous above and on the margin, 
sharp-pointed, the primary 10 to 20 cm. long, 2 mm. wide, those of the innovations 
shorter, the uppermost cauline blades a few millimeters long or reduced to a point; 
panicles narrow, oblong, rather dense, about 5 cm. long, the axis glabrous, the branches 
scabrous, ascending, flower-bearing nearly from base, the ultimate lateral pedicels 
very short (less than 1 mm. long); spikelets about 4-flowered, ovate or elliptical, 
flattened, about 6 mm. long, 3 mm, wide; glumes nearly equal, nearly as long as the 
spikelet, glabrous, acuminate, the first 1-nerved, the second 3-nerved; lemmas oblong, 
firm, acute, glabrous, slightly scabrous at tip of keel, obscurely 5-nerved. 
Type in the U. 8. National Herbarium, no. 454361, collected at Mifiaca, Chihuahua, 
April 1, 1908, by J. N. Rose (no, 11648). 
No other specimens have been observed. This species is allied to Poa chilensis 
Trin.! (not Moris 2), as represented by two specimens in the U.S, National Herbarium, 
one from Chile, distributed by Dr. R. A. Philippi, and one from the province of San 
Juan, Argentina (Kurtz no, 9666). These differ in having longer ligules and abruptly 
acute blades. 
10. Poa strictiramea sp. nov. 
Perennial; culms cespitose, 30 to 40 cm. high, erect, about 3-noded, glabrous; 
sheaths scabrous; ligule 2 mm. long; blades erect, flat or folded, scabrous, 1 to 2 mm. 
wide, those of the innovations 15 to 20 cm. long, those of the culm shorter; panicle 
not much exserted, open, about 10 cm. long, the branches mostly in pairs, slender, 
ascending, the lower stiff, 5 to 6 cm. long, spikelet-bearing toward the ends; spikelets 
tawny, lanceolate, short-pediceled, 3 to 5-flowered, 5 to 6 mm. long; glumes unequal, 
acute, glabrous, scabrous on the keel, the lower 2.5 mm. long, the upper broader, 3.5 
mm. long; lemmas acuminate, faintly nerved, scaberulous all over the back, not cob- 
webby, the lowermost about 4 mm. long. 
Type in the U. 8. National Herbarium, no. 820909, collected on “‘cool ledges of La 
Bufa Mountain above Cusihuiriachic, Chihuahua,’’ Mexico, September 2, 1887, by 
C. G. Pringle (no. 1437). 
Known only from the type collection. 
11. Poa griffithsii sp. nov. 
Perennial; culms cespitose, not producing rhizomes, 50 to 60 cm. high, erect, 
1-noded, scabrous; sheaths scabrous; ligule about 0.5 mm. long; blades firm, pungently 
pointed, flat or folded, scabrous above, glabrous beneath, 1 to 2 mm. wide, those of the 
innovations 15 to 20 cm. long, the lower blades of the culm about 5 cm. long, the upper 
mostly reduced to a mere point; panicles long-exserted, narrow, 6 to 10 cm. long, the 
branches short, appressed, spikelet-bearing from near the base; spikelets pale green or 
tawny, nearly sessile, lanceolate, about 1 cm, long, 3 to 4 mm. wide, about 8-flowered, 
the florets closely imbricated; glumes acute, about 5 mm. long, glabrous, a few serra- 
tions on the keel above; lemmas firm, smooth, slightly serrate on the upper part of the 
keel, the nerves indistinct, no cobwebby hairs at the base; palea shorter than the 
lemma, ciliate-scabrous on the keels. 
Type in the U. S. National Herbarium, no. 691228, collected at Cananea, Sonora, 
July 7-8, 1903, by David Griffiths (no. 4865). 
Rance: Known only from the type collection. 
1Mém. Acad. St. Pétersb. VI. Sci. Nat. 2!: 62. 1836. 
2 Ann. Stor. Nat. Bologna 4: 60. 1830. 
