100 SETARIA VERTICILLATA. 
compressed, almost sessile, clustered, having involucral bristles 
longer than the spikelets, and each strongly dentate, the teeth 
pointing downwards. Glumes very unequal, two. Upper floret 
of two palee. Styles two. Stigmas short and plumose. Stamens 
three. Anthers deep purple in colour. Seeds shining and hard. 
Length from six to twenty-four inches. Root annual and fibrous. 
The involucral bristles are much larger in Setaria viridis. 
Flowers in July, and seeds ripen toward the close of September. 
The specimen for illustration was gathered in Battersea Fields, 
by Mr. J. Sidebotham, of Manchester. 
