128 POACEAE 



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

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

 its branches erect : spikelets 6-8 mm. long, the scales very hispidulous, tlie outer ones 

 about equal, acuminate and awn-pointed, the flowering scale obtuse, the basal hairs from 

 ^-f its length, the awn stout, exceeding or equalling the scale. [C. Niittalliann Steud.] 



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 conv(jlute above, and 

 dense spike-like panicles. Spikelets 1-flowered, the racliilla prolonged beyond tlie 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, attenu;ited 

 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. ) Roth.] 



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

 Great Lakes. Summer and fall. Sea Sand Rj:ed. 



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 Ghass. 



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. [Galamayrostis Cartissu\niiey.~\ 



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 flrst 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 di.stinct. Stigmas 

 plumose. Velvet Grass. 



1. Holcus lanatus L. Softly and densely pubescent. Stems 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 2 mm. long, glabrous, 

 shining, the upper one 2-toothed and bearing a Anally 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. Aira 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. 



