A GUIDE AND KEY TO AQUATIC PLANTS 



37 



40. Leaves grass-like, continued as a sheath below base of Hydrochloa, p. 82. 



blade (fig. 40). 

 40. Leaves not grass-like and not continued as a sheath be- 41. 

 low the base of the blade. 



41. Stems with a sheath (ocreae) just above attach- Polygonum, p. 114. 

 ment point of leaf; flowers individually small, 

 white to pink (fig. 41) 

 41. Stems with no sheaths __ 42. 



Figure 40. 



Figure 41. 



42. Flowers large, showy yellow; fruit a 4-angled capsule Jussiaea, p. 128. 



(fig. 42). 

 42. Flowers small, inconspicuous; fruit a 3-angled nutlet Proserpinaca, p. 129. 



(fig. 7). 



