POACEAE. 53 



Flowering glume awned; spikelets 15-30-flow- 



ered. 2. L. miiUiflorum. 



Annual: empty glume as long or longer than the 



spikelet. 3. //. temulentum. 



1. L. perenne L. (English Rye-grass.) Perennial; culms 

 3-6 dm. high, erect or commonly geniculate at the base, smooth; 

 sheaths smooth; leaves scabrid on the edges and upper side; spike 

 1-3 dm. long, bearing 6-10 spikelets; rachis smooth, channeled; 

 spikelets 6-8 mm. long, smooth, shining, 7-11 -flowered; empty 

 glumes strongly ribbed, much shorter than the spikelet; flowering 

 glume linear-oblong, terete, obtuse to shortly awned, ribbed. 



Occasional in moist places along irrigating ditches and in low 

 ground. Flowering the year round. 



2. L. multiflorum Lam. (Italian Rye-grass.) Perennial; 

 spikes often purplish, somewhat curved; spikelets 15-30-flowered; 

 flowering glumes usually with a short slender awn. 



In similar locations and apparently more common than the pre- 

 ceding. 



3. L. temulentum L. (Darnel.) Annual; culms rather stout, 

 3-8 dm. high, smooth; sheaths smooth, usually somewhat exceed- 

 ing the nodes; spikes stout, with 9-15 spikelets; spikelets 5-7-flow- 

 ered; empty glumes not ribbed, equaling or usually exceeding the 

 spikelets; flowering glume turgid, awnless or commonly with a 

 straight awn 2 cm. long or less. 



Occasional along roadsides and in grain fields. 



Z^. LEPTURUS R. Br. Hard-grass. 



Mostly low annual grasses, with narrow leaves and 

 strict or curved elongated slender spikes; spikelets 1-2- 

 flowered, sessile and single in alternate notches of the 

 jointed rachis. Empty glumes 1-2, narrow, rigid, acute, 

 5-nerved; flowering glumes much shorter, hyaline, keeled, 

 1-sided to the rachis. Palea hyaline, 2-nerved. Sta- 

 mens 3 or less. Styles short, distinct. Grain narrow, 

 glabrous, free, enclosed in the glume. 



1. L. cylindricus Trin. Culms slender, erect, straight, 2-4 dm. 

 high, somewhat tufted, simple or commonly branched, smooth; 

 sheaths smooth, much shorter than the internodes; leaves ascending, 

 1-2 mm. wide, di-^ cm. long, smooth; spike green, 5-15 cm. long, 

 straight; empty glume very acute, about 4 mm. long. 



Occasional on borders of salt marshes toward the coast. Mes- 

 mer; Wilmington; Oceanside. 



2. L. incurvatus (L.) Trin. Culms much branched, internodes 

 more or less curved, more or less purplish throughout; spikes numer- 

 ous, incurved; empty glumes 2, about 6 mm. long, narrow, acute. 



Not known within our limits, but it occurs on the salt marshes 

 at San Diego and about San Francisco. 



