102 FLORA. 



About 8 species, chiefly natives of the Mediterranean region, one or two alss 

 widely distributed through middle Europe and Asia. 



I. Heleochloa schoenoides (L.) Host. Rush Cat-tail Grass. (I F. £ 

 333.) Glabrous. Culms 1-4.5 dm. tall, branched, smooth; sheaths about half tht 

 length of the iiltemodes, the upper loose, the one immediately below the spik« 

 inflated and usually partially enclosing it ; leaves 2.5-7.5 cm. long, 2-4 mm. w 

 flat, acuminate, smooth beneath, scabrous above ; spikelets 2.5 mm. long, tht 

 empty scales acute, compressed, ciliate-keeled, I -nerved ; third scale equalling or 

 longer than the second, acute, compressed, ciliate-keeled, otherwise glabrous, 

 1 -nerved. In waste places, southern N. Y. to Del. Naturalized from Europe. 

 July-Aug. 



34. PHLEUM L. 

 Annual or perennial grasses with flat leaves and spicate inflorescence. Spike- 

 let* 1 -flowered. Scales 3 ; the 2 outer empty, membranous, compressed, keeled, 

 the apex obliquely truncate, the midnerve produced into an awn ; the third scale 

 much shorter, broader, hyaline, truncate, denticulate at the summit ; palet narrow, 

 hyaline. Stamens 3. Styles distinct, somewhat elongated. Stigmas plumose. 

 Grain ovoid, free, enclosed in the scale and palet. [Name Greek, taken from 

 Pliny ; originally applied to some very different plant.] About 10 species, inhab- 

 iting the temperate zones of both hemispheres. The following only are natives of 

 N. Am. The English name Cat-tail Grass is applied to all the species. 



Spikes usually elongated, cylindric ; awns less than one-half the length of the outer 

 scales; upper sheath not inflated. 1. P. pratense. 



Spikes not elongated, ovoid to oblong and cylindric ; awns about one-half the length of 

 the outer scales ; upper sheath inflated. 2. P. alpinum 



1. Phleum pratense L. Timothy. Herd-grass. (I. F. f. 334.) Glabrous 

 and smooth or very nearly so throughout. Culms 3-12 dm. tall, erect, simple; 

 sheaths usually exceeding the internodes, sometimes shorter, the upper one long 

 and not inflated, or very slightly so ; leaves 7.5-22.5 cm. long, 4-6 mm. wide, 

 smooth or scabrous ; spike usually elongated, cylindric, 3-75-17-5 cm. in length, 

 5-8 mm. in diameter ; outer scales of the spikelet, exclusive of the awn, 2-5 mm. 

 long, ciliate on the keel, the awn less than half their length. In fields and mead- 

 ows nearly throughout N. Am. Also in Europe and Asia. Widely cultivated for 

 hay. The scales are sometimes modified into small leaves. July-Aug. 



2. Phleum alpinum L. Mountain Phleum. (I. F. f. 335.) Glabrous. 

 Culms 1.5-4.5 dm. tall, erect or sometimes decumbent at the base, simple, smooth; 

 sheaths often much shorter than the internodes, sometimes longer, the upper one 

 usually much inflated ; leaves smooth beneath, scabrous above, the lower 5-7.5 

 cm. long, 2-8 mm. wide ; upper leaf generally very short, less than 2.5 cm. long ; 

 spike short, ovoid to oblong and cylindric, 1.25-5 cm. in length, 6-12 mm. in 

 diameter ; outer scales of the spikelet, exclusive of the awn, 3 mm. long, strongly 

 ciliate on the keel, the awn about one-half their length. Lab. to Alaska, south to 

 the mountains of N. H., Vt., Ariz, and Cal. Also in northern Europe and Asia and 

 in Patagonia. Summer. 



35. ALOPECURUS L. 



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

 and spicate inflorescence. Spikelets 1 -flowered, flattened: scales 3, the 2 lower 

 empty, acute, sometimes 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, subtending 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, signifying 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 N. Am. 



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



1. A. agrestis. 

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

 keel. 



