dorsal 

 groove 



Figure 2. 

 Alisma plantago-aguatica var. parviflorum: A. habit 

 of emersed plant, x Vt. B. habit of submersed plant, x 

 V2. C. flower, X 2. D. fruiting head, x 4. E. achene, side 

 view, X 8. F. achene, end view, x 8. 

 var. atnericanum: G. flower, x 2, 



