108 



Fig. 404. CenchrusgracillimusXash, Bull. Torr. Bot. Club. 22 : 

 300. 1895. Slender Sand-bur. — An ascending, sparingly 

 branched, slender, leafy annual 3 to 6 dm. high, with loosely 

 flowered, slender spikes 3 to 5 cm. long. Involucre (b) ovate, 

 smooth, with numerous long, slender, usually purplish spines. — 

 High pine lands, Florida. April-September. 



