68 ADDISONIA 
completely covering lakes and ponds; this has similar, somewhat 
larger flowers, but its petioles are inflated and bladder-like, enabling 
the plant to float freely. Both species show trimorphism, having 
stamens and styles of three different lengths in different flowers. 
Both are in cultivation under glass at the New York Botanical 
Garden, and are also grown here in a pond at the herbaceous 
garden during the summer, where the first touch of frost kills them 
promptly. 
The plant here illustrated was sent to us from Fairmount Park, 
Philadelphia, in 1905 
N. IL. Britron. 
EXPLANATION OF PLATE. Fig. 1.—Flowering stem. Fig. 2,—Flower opened. 
Fig. 3.—Leaf. 
