340 
CHAPTER XX. 
Plate XXXV. — vallisneria. 
Fig. 1. Valisneria spiralis. The female plant , the flowers of 
which are purple. This is drawn from a specimen in the posses¬ 
sion of Dr. Ogle. 
Fig. 2. The male plant , producing white flowers; these when 
mature rise like air bubbles, and suddenly expanding when they 
reach the surface of the water, float about in such abundance as to 
cover it entirely. “ Thus their pollen is scattered over the stigmas 
of the first mentioned blossoms, whose stalks soon afterwards re¬ 
sume their spiral figure, and the fruit comes to maturity at tb* bot¬ 
tom of the water.” 
Fig. 3. One of the separated male flowers magnified. 
