PLATE XVI. 



1 



Stem leaves, bracts, petals, capsules, and flowers of Onagra biennis and of two of 

 the four hybrid types of Onagra lamarckiana X Onagra biennis. 



i, Onagra biennis ; 2, No. 2.27; 3, No. 2.32. Stem-leaves one-fourth natural size; remainder of 



figures five-eighths natural size. 



