324 



COMMON WEEDS 



The following are some of the more important weeds 

 of ditches, ponds, and streams : 



RANUNCULACE^E 



Water Crowfoot. Under this name may be grouped 

 a number of aquatic Rammculi, which from a botanical 

 point of view are closely related and difficult to dis- 



FIG. 91. Water Crowfoot (Ranunculus peltatus Fries.), nat. size. 



tinguish from each other. They have white flowers 

 with a yellow centre ; most of them have stems many 

 feet long ; in some species only submerged, finely 

 divided leaves are present, while others have in addition 

 leaves with flat-lobed segments which float on the sur- 

 face of the water. 



The following may be noted : 



R. heterophyllus Fries. Floating leaves, three- to five- 

 lobed, nearly circular in outline ; submerged leaves, 



