EXPLANATION OF PLATE 4. 

 Hazelnlt [Corylus calif omlca) . 



The main figure is a fruiting branch. Above at the left are two staminate catkins, 

 with a pistillate flowering l)ud at their base, accompanied by a sectional view of a 

 catkin scale and stamens, enlargetl six times. To the right above are a terminal bud 

 and a nut. Underneath the main figure are views of catkin scales and stamens, from 

 front and back, six times natural size, and at the right a terminal cluster of pistillate 

 flowers, enlarged three times. Except in the cases noted, the figures are of natural 

 size. 



Drawing t)y Frederick A. Walpule. 



