24 INTRODUCTION 



in a fresh flower with a viscid liquid to which 

 the pollen grains readily adhere. 



EVENING PRIMROSE 



The blossoms of this plant generally first open 

 in the evening. The process may be readily seen 

 by a little patient watching: the tips of the sepal- 

 lobes spread apart and soon afterward the petals 

 expand. At this time the flower is fully open 



