T mi: (in a ss ks ok T i: n n i:ss i : i:. 'A 1 



3. Paspalum distichum I.. Knot-^M-ass. 



A prostrate, extensively creepinj^ and much-branched ^rass, the 

 ascending extremities of the stems and frecjuent sterile or flower- 

 bearini^ leafy shoots, six toeij^htecn inches hij^h. Sheaths smooth 

 or ciliate alon^- the margins and at the throat and base; lis^iile 

 short; leaf-blade flat, lanceolate, acute, one to six inches lonj^. one 

 to three lines wide, smooth. Racemes in pairs close together at 

 the apex of the culm or its branches, one to two inches long-, 

 rarely a third raceme below; rachis narrow (one half to one line) 

 flat, smooth. Spikelets oblonjj, acute, about one and one-half 

 lines lon^, in two close rows, nearly sessile, outer jjlumes acute, 

 three- to five-nerved, usually thinly and minutely pubescent, a lit- 

 tle longer than the acute floral glume which is minutely bearded 

 at the tip. There is sometimes a third outer glume at the base of 

 the spikelet, either rounded and minute or narrow-lanceolate, 

 acute one-nerved and one-half to three-fourths as long as the spike- 

 let. 



Moist, usually sandy soils; along river banks, margins of ponds, 

 "sink-holes," etc. June to October. 



This grass is very widely distributed over the tropical and 

 warmer temperate regions of the world. Probably introduced 

 from the South into Tennessee. It has much the same habit of 

 growth as Bermuda grass, but the stems are coarser and the flow- 

 ering racemes are stouter and nearly always in pairs. It is valu- 

 able for holding loose sands where there is moisture, and for cov- 

 ering the soil of "sink-holes" where other grasses usually die out. 



4- Paspalum platycaule Poir. (P. coffipressiDn Nees.) Carpet- grass 

 or Louisiana-grass. 



Plate VII. Figure 25. 



A slender, erect, or more frequently prostrate and extensively 

 creeping perennial, rooting at the nodes and sending up numer- 

 ous leafy or flower-bearing branches, six to twenty-four inches 

 high. Culm and branches strongly flattened. Sheaths com- 

 pressed, the lower imbricate, smooth; ligule short, ciliate; leaf- 

 blade linear or narrowly lanceolate, two to ten inches long, one to 

 three lines wide, smooth, scabrous on the margins near the 

 rounded or blunt apex. Racemes tw^o to six, subdigitate, one or two 

 of the lower sometimes remote, one to three inches long, slender, al- 

 most filiform, erect or ascending; the apex of the culm frequently 

 divides into two or three flower-bearing branches, which, with the 

 main axis, issue from the upper leaf-sheath; rachis of the racemes 

 very narrow (one-fourth of a line) somewhat flexuose, smooth. 

 Spikelets elliptical, about one line long, subacute, biseriate, 

 scarcely imbricate, closely appressed to the rachis, smooth or more 

 or less hairy; first glume four-nerved, two nerves near each margin, 

 the second two-nerved; flowering glume obtuse, minutely pubes- 

 cent at the apex and with a distinct depression on the back near 

 the base. 



