148 GRAMINEAE. 



2. Phleum alpinum L,. Mountain Phleum. (Fig. 335.) 



Phleum alpinum L,. Sp. PI. 59. 1/53. 



Glabrous, culms 6 / -iS / tall, erect or sometimes de- 

 cumbent at the base, simple, smooth. Sheaths often 

 much shorter than the internodes, sometimes longer, 

 the upper one usually much inflated; ligule about 

 i // long, truncate; leaves smooth beneath, scabrous 

 above, the lower 2 / -3 / long, 1"-^" wide; upper leaf 

 generally very short, less than i' long; spike short, 

 ovoid to oblong and cylindric, / I -^ / -2 / in length, 3 // -6 // 

 in diameter; outer scales of the spikelet, exclusive of 

 the awn, ij^ // l n g. strongly ciliate on the keel, the 

 awn about one-half their length. 



I/abrador to Alaska, south to the mountains of New 

 Hampshire, Vermont, Arizona and California. Also in 

 northern Europe and Asia and in Patagonia. Summer. 



29. ALOPECURUS L. Sp. PI. 60. 1753. 



Annual or perennial grasses with erect or decumbent culms, usually flat leaves, and spi- 

 cate inflorescence. Spikelets i-flowered, flattened; scales 3, the 2 lower empty, acute, some- 

 times short-awned, more or less united below, compressed -keeled; keel ciliate or somewhat 

 winged; third scale truncate or obtuse, hyaline, 3-nerved, awned on the back, subtend- 

 ing a perfect flower and usually a palet; palet hyaline, acute, sometimes wanting. Stamens 

 3. Styles distinct or rarely united at the base. Stigmas elongated, hairy. [Greek, signify- 

 ing Fox-tail Grass, in allusion to the spikes.] 



About 20 species, principally natives of the north temperate zone. Besides the following, some 

 4~others occur in western North America. 



Outer scales of the spikelet united for one-half their length, smooth to hispid on the keel. 



i. A. agrestis. 



Outer scales of the spikelet united for one-quarter their length or less.long-ciliate on the keel. 

 Scales i"-i#" in length. 2. A. geniculatits. 



Scales 2" -3" in length. 



Spike i W-zYi' long; outer scales glabrous or sparingly pubescent on the lateral nerves. 



3. A. pratensis. 

 Spike 1 1 A' long or less; outer scales villous. 4. A. alpinus. 



i. Alopecurus agrestis I,. Slender Foxtail. (Fig. 336.) 



Alopecurus agrestis I<. Sp. PI. Ed. 2, 89. 1762. 



Smooth or slightly scabrous, culms i-2 tall, erect, 

 simple. Sheaths shorter than the internodes ; ligule 

 i" long, truncate; leaves i^'-j' long, \"-$" wide, 

 scabrous, especially above; spike i^-4'long, 2 // -4 // 

 thick ; outer scales of the spikelet united at the base 

 for about half their length, narrowly wing-keeled, 

 2 // -2^ // long, the nerves smooth or scabrous, some- 

 times hispid below, especially on the keel; third scale 

 equalling or slightly exceeding the outer ones, smooth 

 and glabrous, the awn inserted near the base, about 

 twice its length, bent. 



In waste places and ballast, southern New York and 

 New Jersey. Adventive from Europe. Native also of 

 Asia. July- Aug. 



