128 POACEAE 



2. Calamagrostis cinnoides (Muhl.) Scribn. Stems 9-15 dm. tall, erect: leaf- 

 blades 1-3 dm. long or more, 4-10 mm. wide, rough : panicle 7-18 cm. long, contracted, 

 its 

 about 



H 



In moist soil, New Hampshire and Massachusetts to Pennsylvania and Georgia, Summer. 



66. AMMOPHILA Host. 



Tall perennial grasses, with flat leaf-blades, which are often convolute above, and 

 dense spike-like panicles. Spikelets 1 -flowered, the rachilla prolonged beyond the flower 

 and hairy. Scales 3, rigid, chartaceous, acute, keeled ; flowering scale 5-nerved, with a 

 ring of short hairs at the base. Stamens 3. Styles distinct. Stigmas plumose. 



1. Ammophila arenaiia (L.) Link. Stems 6-12 dm. tall, erect, rigid, stout, arising 

 from a long branching rootstock : leaf -blades 1.5-3 dm. long or more, rigid, attenuated 

 into a long slender involute point, rough above : panicle 1-3 dm. long, 1-1.5 cm. in diam- 

 eter : spikelets 10-12 mm. long, the scales hispidulous, the flowering scale usually with the 

 rudiment of an awn just below the apex. [Calamagrostis arenaria ( L. ) Koth.] 



In sands along the seacoast, New Brunswick to North Carolina, and inland along the shores of the 

 Great Lakes. Summer and fall. SEA SAND REED. 



67. CALAMOVILFA Hack. 



Tall perennial grasses, with horizontal rootstocks, elongated narrow flat leaf-blades, 

 involute at the apex, and contracted or open panicles. Spikelets flattened, 1 -flowered, 

 crowded, the rachilla articulated above the empty scales and not prolonged beyond the 

 flower. Scales 3, rigid, chartaceous, awnless, keeled, 1-nerved, the 2 outer empty, unequal, 

 persistent, the third scale with a ring of long hairs at the base, enclosing a 2-keeled palet 

 and a perfect flower. Stamens 3. Styles distinct. Stigmas plumose. REED GRASS. 



1. Calamovilfa Curtissii Vasey. Stems 8-12 dm. tall, erect : leaf-blades 4 dm. long 

 or less, 2-3 mm. wide : panicle 1.5-3 dm. long, narrow, 1.5-2 cm. in diameter, its branches 

 erect : spikelets about 5 mm. long. [Calamagrostifs Curtissii Vasey.] 



In dry or moist pine lands along the Indian River, Florida. Summer. 



68. HOLCUS L. 



Annual or perennial grasses, with usually flat leaf-blades and terminal spike-like con- 

 tracted or open often interrupted panicles. Spikelets crowded, 2-flowered, the lower flower 

 perfect, the upper one staminate, the rachilla articulated below the empty scales. Scales 

 4, the 2 outer empty, keeled, the first 1-nerved, acute, the second broader, 3-nerved, acute 

 or short-awned, the third and fourth scales shorter than the second, membranous, at length 

 rigid, enclosing flowers, the former awnless, the latter bearing a slender dorsal awn which 

 is often hooked when dry; palet narrow, 2-keeled. Stamens 3. Styles distinct. Stigmas 

 plumose. VELVET GRASS. 



1. Helens lanatus L. Softly and densely pubescent. Steins 4-9 dm. tall, erect, 

 tufted : leaf -blades 2.5-15 cm. long, 4-12 mm. wide : spikelets 4 mm. long, the empty 

 scales white-villous, the upper one awn-pointed, the flowering scales 2mm. long, glabrous, 

 shining, the upper one 2-toothed and bearing a finally hooked awn just below the apex. 



In meadows, fields and waste places, Nova Scotia to Ontario, Illinois, North Carolina and Tennes- 

 see. Also on the Pacific Coast. Naturalized from Europe. Summer. VELVET GRASS. 



69. AIRA L. 



Mostly annual grasses, with narrow leaf-blades and contracted or open panicles. 

 Spikelets small, 2-flowered, both flowers perfect. Scales 4, the lower 2 empty, thin-mem- 

 branous, acute, subequal, persistent, the flowering scales usually close together on the 

 rachilla, hyaline, mucronate or 2-toothed, bearing a delicate awn inserted just below the 

 middle. Stamens 3. Stigmas plumose. HAIR GRASS. 



1. Aha caryophyllea L. Glabrous throughout. Stems 1-2.5 dm. tall, erect, from 

 an annual root, slender : leaf-blades 1-5 cm. long, involute-setaceous : panicle silvery, 

 shining, 2-10 cm. long, open, its branches spreading or ascending : spikelets 2-2.5 mm. 

 long, the empty scales acute, the flowering scales very acute, 2-toothed, 2 mm. long, bear- 

 ing an awn 3-4 mm. long. 



In fields and waste places, Massachusetts to North Carolina. Also on the Pacific Coast. Natural- 

 ized from Europe. Spring and summer. 



