GRAMINEAE 15 



b. Flowering scales rounded on the back, at least below : hilutn 

 linear. 58. Festuca. 



B. Stigmas plainly inserted below the apex of the ovary. 



59. Bromus. 

 Tribe XI. HORDEAE. 

 Spikelets singly arranged at the rachis-nodes. 

 Spikelets with the flowering scales with their backs to the rachis : empty 



scale I. 60. LOLIUM. 



Spikelets with the flowering scales with their sides to the rachis : empty 

 scales 2. 

 Spikeletsi-2-flowered, in slender, jointed spikes. 61. Lepturus. 

 Spikelets 2-many-flowered, in stout, joiutless spikes. 



62. Agropyron. 

 Spikelets 2-6 at each rachis-node : 

 i-flowered. 63. Hoedeum. 



2-many-flowered. 

 Empty scales usually as long as the flowering ones. 64. Elymus. 

 Empty scales wanting or minute. 65. HyStrix. 



1. TRIPSACUM L. 



1. Tripsacum dactyloides L. Gama Grass. (Man. p. 67; I. P. 

 /. 210.) In swamps and on shaded banks, Conn, to Kans., Fla., Tex. 

 and Neb. — Pennsylvania : Berks, near Reading ; Chester ; LANCASTER. 



2. ERIANTHUS Michx. 



1. Erianthus compactns Nash. Contracted Pi,umEGRASS. (Man. 

 p. 68 ; I. F. / 2/3.) In moist soil, N. J. and Pa. to N. C. and Tenn. — 

 Pennsylvania : Bucks. 



3. ANDROPOGON L. 



Racemes singly disposed ; rachis-internodes appendaged at the apex. 



1. A. scoparius. 

 Racemes 2 or more together : rachis internodes not appendaged. 

 Pedicellate spikelet as large as the sessile one or larger, consisting of 4 scales, 



a staminate flower, or rarely a perfect flower. 2. A. furcatus. 



Pedicellate spikelet much smaller than the sessile one, sterile, with i or 2 

 scales. 

 Inflorescence with its branches not much divided nor the lower branches 

 not excessively elongated, hence long and narrow : upper stem-leaves 

 usually shorter than the inflorescence. 3. A. Virginicus. 



Inflorescence with its branches many times divided, the lower ones elon- 

 gated, thus forming a corymbiform mass or masses : upper stem-leaves 

 usually exceeding the inflorescence. 4. A. corymbosus. 



1. Andropogon scoparius Michx. Broom Beard-grass. (Man. p. 



69 ; I. F. /. 216.') In sandy soil, N. B. to Fla., Ala. and Texas. — Penn- 

 sylvania : Dei<aware ; Chester ; Phii<adei/Phia ; Bucks ; Lancas- 

 ter ; Northampton ; Luzerne ; Dauphin ; Ai,i,egheny. 



2. Andropogon furcatus Muhl. Forked BEard-grass. (Man. p. 



70 ; I. F. /. 2/9. ) In dry or moist, often stony soil. Me. and Ont. to 

 Man., Fla. and Tex. — Pennsylvania: Dei<aware; Chester; Phii,a- 



