TRIANDRIA. DIGYNIA. 55 



Hed to Cenchrus, and furnished with a spiny involucrum.) 

 2. lcevig-atu?n. El. o. glancum. 4. viride. 5. verticillatwn. 

 (These two last appear to have been introduced.) 6. cor- 

 riigaUim. 7- Italiciim. (This species is supposed to be the 

 true Panicum of the ancients, and its drooping panicle is 

 described by Pliny, who speaks of it as not so much used 

 as the Millet {Panicum miliaceum) in making' bread, but 

 weighing rnore than any other grain, as well as increasing 

 more in bulk when cooked. It is still cultivated in Italy 

 and other parts of Europe, and from the vast size of its 

 spike must be very productive. Mr. Elliott remarks, that 

 in Carohna it sometimes attains the height of lO feet. Of 

 this genus, though not numerous, there are species in 

 Europe, India, the West Indies, Africa, andNew Holland. 



81. ORTHOPOGON. Mr. R. Brown, 



Calix 1 -flowered, with 3 nearJy equal valves, 

 all awned, the awn of the exterior valve much 

 longer than the others,- awns straight, and 

 smooth. 



With the exception of the present species, these are 

 tropical grasses, growing in siiady places. Their leaves 

 flat, and broadish. Spike composed of alternate spikelets 

 directed all one way, and sometimes consisting of very 

 few flowers. 



Species. 1. O. hirtellum. {Panicuin hirteUnm, Lix.) In 

 Florida and South Carolina. In this species, as it appears 

 in the United States, the spikelets contain from 5 to 8 

 flowers, the partial and general rachis often smooth as 

 well as villous, sometimes the valves of the calix aremul- 

 tiphed to 4, of which the external ones whether above or 

 below are furnished with very long, smooth, straight, and 

 'viscid awns; the neutral rudiment at the base of the inner 

 valve of the indurated perfect flower is very minute and 

 bifid, constantly attended with an oblique and imperfect 

 lateral valve, ciliate at the upper edge as are all the^ alves 

 of the calix, whether the other pubescence be present or 

 not. Of this genus Mr. Urown describes 4 species in 

 New Holland, the P. compositum of Cey\or\ as well as the 

 present plant are also included in this genus by its foun- 

 der, and there appears to be some other species in India 

 and the West India islands. 



§2. DIGITARIA. Hfl//er. Richard, (Crab-grass.) 



Calix 2 or 3-valvetl, concave; exterior valve 



minute; or none^ second variable; the innermost 



