406 WEEDS AND USEFUL PLANTS. 



ovoid-oblong, yellowish-green ; bristles 4 - 8 in a cluster, about as long 

 as the spikelets ; paleae of the perfect floret smooth, striately punctate. 



ITALIAN SET ARIA. Millet. Bengal Grass. 



Root annual. Culm 2 - 4 or 5 feet high. Leaves 6 - 12 and 18 inches long, lance-linear, 

 rather broad, flat, serrulate on the margin ; sheaths striate, pubescent on the margin ; 

 ligule beard-like. Spite compound (or rather a densely contracted panicle) ,3-6 inches 

 long, ovoid-oblong or sub-cylindric ; rachis densely hirsute with long hairs. Bristles some- 

 times longer than the spikelets, yellowish. Sterile floret wholly abortive, or neutral, the 

 upj)erpalea very minute, palece of the perfect floret smooth, minutely striate-piinctate. 



Fields ; cultivated as a fallow crop. Native' of Europe and India. Fl. July. Fr. Aug. 



Obs. Some years ago, the culture of this plant was introduced into 

 Pennsylvania, and excited considerable interest, for a time, among the 

 farmers, as affording valuable fodder, when the usual hay- crop was 

 likely to be deficient. It was soon found, however, not to be as valuable 

 as the usual fallow crop (of Oats or Barley), of which it occupied the 

 place ; and was, moreover, remarkably liable to damage from rain. The 

 cultivation, therefore, soon declined. and is now generally abandoned. 

 There is another species (S. verticillata, Beauv., with the spike com- 

 posed of interrupted verticils of spikelets, and the involucre of retrorsely 

 scabrous bristles, in pairs.) which is becoming something of a nuisance, 

 about gardens, in many places ; but it seems scarcely, as yet, entitled to 

 a more particular notice here. 



30. CEN'CHRUS, L. BUR GRASS 



[Greek, Kenchros ; the ancient name of Millet.] 



Spikelets as in Panicum, awnless, but enclosed (1-5 together) in a glob- 

 ular bristly or spinose involucre, which becomes coriaceous, forming a 

 deciduous bur in fruit. Involucres sessile in a terminal spike. Styles 

 united below. 



1. C. tribulpi'des, L. Involucre subglobose, pubescent, spinosely 

 muricate, split on one side. 



TRIBULUS-LIKE CENCHRUS. Bur Grass. Hedge-hog Grass. 



Root annual. Culm 1-2 feet long, usually oblique or procumbent, geniculate, branch- 

 ing, smooth. Leaves 3-6 or 8 inches long, lance-linear, acuminate, slightly scabrous on 

 the margin ; sheaths loose, smooth ; ligule beard-like. Raceme terminal, of 6-12 or 14 

 alternate involucrate heads or clusters ; rachis angular, flexuose, slightly scabrous. In- 

 volucre urceolate or subglobose, laciniate, usually split to the base on one side, hairy, 

 armed externally with rigid subulate scabrous spines, villous within, embracing 1, 2, or 

 3 spikelets. Sterile floret mostly staminatc. Sandy fields. Fl. Aug. Fr. Sept. 



Obs. The plant is very abundant in sandy districts along the coast and 

 around the great Lakes, and has found its way to some of the slaty 

 hills of Pennsylvania. It is altogether a worthless grass ; and the 

 prickly involucres are a grievous nuisance, wherever it prevails in cul- 



