38 GEAMINE^. 



BF^ptlet usually hyaline or membranous at maturity (at least not remarkaljly 

 firmer in texture than the bracts); panicle various, but usually contracted, 

 dense and spikelike. 

 Pedicel jointed below the bracts, so that these fall a nay with the flower at 

 maturity, sometimes together with the whole or a part of the pedicel. 



Bracts awnless . . .10. Alopecdhus. 



Bracts long-awned 11. Polyfoqon. 



Pedicel not jointed below the bracts; rachilla jointed above the bracts so that 

 these persist after the flower has fallen, 

 gpikelets 3 lines or less long. 

 Rachilla naked or with a few very short hairs. 

 Bracts strongly keeled. 

 Bracts abruptly acute, complicate, ciliately fringed on the keels . . 



9. Phleum. 

 Bracts acuminate, saccate at the base, two-thirds longer than the 



bractlet 13. Gabteidium. 



Bracts not keeled; acute or acuminate; very small . J 2. Agrostis. 

 Rachilla with a tuft of long hairs on the callus, about i the length of the 



bractlet 14. Calamageostis. 



Spikelets 5 to 6 lines long; bractlet and palea chartaceous; a tall sand-dune 

 grass . .15. Ammophila. 



8. STIPA L. 



llootstock tufted. Leaf-blades narrow, involute or convolute. 

 Panicle lax, mostly open or somewhat contracted. Spikelets 

 1-flowered. Bracts subequal, keeled, often terminated by a long sub- 

 ulate point, persistent; rachilla jointed above the bracts. Bract- 

 let and palea dissimilar; bractlet firm, narrow, rolled around the 

 flower, with a terminal, undivided, bent, persistent awn, spirally 

 twisted below the bend; palea usually shorter, thinner, 2-nerved. 

 Scales usually 3 and large. Stamens usually 3, rarely only 1 or 2; 

 anthers often tipped with a tuft of short hairs. Ovary stipitate, 

 smooth; styles 2, short; stigmas plumose with simple hairs. (Greek 

 stipe, feathery, referring to the long, feathery awns of some species. 

 Ours usually met with on dry hillsides. One of the several genera 

 known as " Bunch-grasses.") 



Awn 2% to 4 in. long . . . , . . . . 1. S. sdigera. 



Awn less than 2 in. long. 

 Panicle open, branches spreading; anthers tipped with a tuft of short hairs. 



2. »S. emineni^ 



var. ATidersoni. 



Panicle strict, narrow; branches short, erect; anthers naked . . 3. S. viridula. 



1. S. setigera Presl. Bbar-qrass. Perennial; stems erect, 1 to 

 3 ft. high, slender;, panicle 5 to 12 in. long, open, nodding in flower; 

 branches in pairs, slender, bearing a few drooping spikelets; bracts 6 

 to 10 lines long, long-acuminate; bractlet 3 lines long, silky-hairy 

 sometimes all around below, but only on the nerves above, minutely 

 tuberculate; awn stoutish, 2| to 4 in. long, haiiy below. 



Common on dry hillsides from Mendocino Co. southward: Berkeley 

 hills; San Francisco. Mar.-June. 



2. S. eminens Cav. var. Anderson! Vasey. Anderson's Stipa. 

 Perennial; stems erect, 1 to 3 ft. high, slender; panicle 2 to 5 in. 

 long, open, nodding in flower; branches in pairs, very short, slender, 

 spreading, bearing few drooping spikelets; bracts 3 to 4 lines long, 

 Mcuminate; bractlet about 3 lines long, silky-hairy all over; awn 



