244 BULLETIN 772, U. S. DEPARTMENT OF AGRICULTURE. 
erect annual, 2 to 4 feet tall, with a dense, bristly, yel- 
low or purple head. There are many varieties in culti- 
vation, differing in the size and lobing of the head, the 
length and color of the bristles, and the color of the 
seed. Small forms resemble C. viridis, but may be dis- 
tinguished by the articulation of the seed. In C. viridis 
the seed (fruit, that is, the fertile floret) falls from the 
pedicel inclosed within the glumes. In (C. ééalica the 
seed readily separates from the 
glumes by an articulation above 
the sterile lemma. A ripe head 
of C. italica rubbed between the 
palms yields free seed. A head 
of C. viridis will yield entire 
spikelets. 
Fig. 148.—Yellow foxtail, Chaetochloa lutescens. Plant, X 4%; two views of spikelet 
and fertile floret, x 10. 
The varieties of Chaetochloa italica cultivated in the United States 
have been classified as follows? (under Setaria italica) : 
Fruit dark colored (reddish or orange to blackish or brownish black). 
Hriity reddish or, oranges See xee ene eels eee —_rubrofructa. 
Fruit blackish, brownish black, or purplish black with pale yellowish 
straw lines intermingled, these sometimes predominating_nigrofructa. 
1 See Hubbard, Amer. Journ. Bot. 2: 187. 1915. 
