77 



Glumes of the barren spikelets four or fewer, the outer one the 

 largest and many-nerved, the second keeled, the third and fourth, 

 when present, small, thin, and hyaline, all awnless. 



Styles distinct. 



Grain enclosed in the glumes, but free from them. 



Grasses usually tall and often scented, simple or paniculately 

 branched. 



SECTION I. GYMNANDROPOGON. 



Spikes two, three, or more, clustered at the end of a peduncle without sheathing bracts, 

 very rarely reduced to a single spike. 



Spikelets concealed or nearly so under copious long silky hairs. 



Spikes about 3 inches, spikelets about 3 lines long 1. A. erianthoides. 



Spikes not above 2 inches, spikelets scarcely 2 lines long. 

 Long silky hairs on the back of the outer glumes as well as 



on the rhachis and pedicels ... ... ... ... ... 2. A. sericeus. 



Long silky hairs only or chiefly on the rhachis and pedicels. 



Glumes not pitted... ... ... ... , ... ... 3. A. affinis. 



Outer glumes marked with a pit on the back... ... ... 4. A. pertusus. 



Spikes silky-hairy, but the hairs not covering the spikelets. 



Spikes numerous, the common axis elongated ... ... ... 7. A. intermedius. 



SECTION II. CYMBOPOGON. 



Spikes two together on each peduncle within or above a sheathing bract. 



Spikes both sessile at the end of the peduncle. Awns slender, 



short and glabrous or deficient. 



Silky hairs long, concealing the spikelets or nearly so. Spikes at 

 length spreading or reflexed. Awns none or very fine 

 and scarcely projecting ... ... ... ... ... 11. A. bombycinus. 



Hairs minute. Spikes soon reflexed. Awns very short or none .. 13. A. refractus. 

 One spike affixed lower down than the other, slightly hairy. 



Awns 1 to 3 inches long, hairy on the lower part .., 14. A.lachnatherm. 



1. Andropogon erianthoides, E.v.M. 



Botanical name. Andropogon Greek, andros, of man (man's), 

 pogoiij a beard, in allusion to the tufts of hairs on the inflorescence, 

 thought to resemble a man's beard. Erianthoides , from two Greek 

 words signifying resembling a grass of the genus Erianihus. 



Vernacular name. " Satin Top," or " Satin-topped Grass " ; 

 " Blue Grass," the leaves having a somewhat bluish tinge. 



Where figured. Bailey, Agricultural Gazette. 



Botanical description (B. FL, vii, 529). An erect glaucous, grass of 

 2 or 8 feet, glabrous except the inflorescence, the nodes not bearded. 



Leaves rather narrow. 



Spikes usually three or four, nearly sessile at the end of a peduncle without sheathing 



bracts, erect or scarcely spreading, about 3 inches long. 

 Spikelets concealed under the very copious long silky hairs surrounding the sessile 



spikelet on the pedicels and a few on the outer glumes. 

 Sessile spikelet about 3 lines long. 



Outer glume nearly equally many-nerved, with a short scarious often notched tip. 

 Second glume rather shorter, keeled, three-nerved, acute. 

 Third thin and hyaline. 

 Awn or terminal glume fine, not above twice the length of the spikelet, contracted 



at the base into a flexuose stipes, with sometimes a very slight hyaline dilatation. 

 Pedicellate spikelet reduced to one or two empty glumes. 



Value as a fodder. An excellent grass, nutritious and palatable, 

 yielding a large quantity of rich fodder. 



