34 



PUBLIC HEALTH BULLETIN NO. 286 



26. Leaves in rosettes which float on the surf ace of the water. 27. 

 26. Leaves not in rosettes floating on the surface of the water. 28. 



27. Petioles of leaves greatly inflated (fig. 26) Eichhornia, p. 107. 



27. Petioles not inflated (fig. 27) Limnobium, p. 76. 



Figure 26. 



Figure 27 



28. 



28. 



30. 

 30. 



Leaves arising from points along a horizontal stem, 29. 

 this stem being either buried under the substratum 

 or lying procumbent along it. 

 Leaves from lax stems which float in the water with 34. 

 the leaves. 



29. Leaves peltate 30. 



29. Leaves not peltate 32. 



Leaves round 31. 



Leaves elliptic, the petiole and under surface coated Brasenia, p. 117. 

 with a thick jelly-like material (fig. 28). 



31. Leaves small, about 8 cm. in diameter or less; Hydrocotyle, p. 130. 



toothed or lobed (fig. 29). 

 31. Leaves large; more than 20 cm. in diameter; Nelumbo, p. 117. 

 margins entire and impossible to wet leaf 

 (fig. 30). 



Figure 28. 



x'/2 

 Figure 29. 



Figure 30. 



