So6 BOTANICAL GAZETTE [june 



Several other species described by Greene and based upon 

 characters seemingly inconsistent or difficult at present to evaluate, 

 are reserved for later treatment. 



University of Chicago 



EXPLANATION OF PLATE XXXI 



Bidens mirabilis. — a, spray Xo. 7; b, exterior bract X4; c, interior bract X4; 

 d,paleaX4; e, floret X 7; /, anther X 3 5; g, pollen grain X350; h, achene X 1 1 ; 

 i, portion of leaflet X3; all from type in Herb. Kew. 



