BIOLOGICAL CLASSIFICATION [CH. i 



B. Plants entirely or partially submerged. 



(i) Rooted, but roots not penetrating the soil. Floating 

 shoots, formed at flowering time, which raise the flowers 

 into the air. 



Lemna trtsulca^ L. (Ivy-leaved Duckweed), 

 (ii) Rootless. 



(a) Inflorescence raised out of the water. 



Aldrovandia. 



Utricularia (Bladderwort). 

 () Flowers submerged; hydrophilous pollination. 



Cer atop hy Hum (Horn wort). 



