FLOWERING PLANTS AND FERNS OF INDIANA. 621 



P. ZiznKoth. 



In ponds and sluggish streams in the northern counties of the 

 State. Of sparing occurrence in its stations. 

 Flowers in July and August. 

 Lake (Hill). 



P. ltjcens L. Shining Pondweed. 



Found locally in ponds and swamps in a few counties of the State. 

 Flowers in September and October. 

 Steuben (Bradner) ; Gibson. 



P. prjelongus Wulf. White-stemmed Pondweed. 



Reported only from the northern part of the State by E. J. Hill, 

 though probably of wider distribution. 



It fruits in June and July and usually withdraws its stems beneath 

 the water as soon as the fruit is set. 



Lake (Hill). 



P. perfoliatus Kichardsonji A. Bennett. 



(P. perfoliatus lanceolatus Robbins.) 

 In the northern counties in ponds and streams. Probably of 

 wider distribution than reports indicate. 

 Flowers in July and August. 

 Laporte (Hill . 



P. zosters folius Schum. Eel-grass Pondweed. 



Common throughout the State, usually in still water, though 

 occasionally found in quite swift streams. 

 Flowers in July and August. 

 Laporte (Barnes) ; Steuben (Bradner) ; Lake (Hill); Carroll. 



P. foliosus Raf. 



(P. paucifloriis Pursh. ) 

 Throughout the State, in shallow ponds and ditches Usually 

 abundant iu the stations in which it occurs. 

 Fiowers in July and August. 



Jasper (J. M. Coulter ) ; Hamilton ( Wilson) ; Fayette ( Hessler) ; 

 Vigo (Blatchley); Jefferson and Gibson. 



P. foliosus Niagarensis (Tuckerm.) Morong. 



(P. paucifloriis Xiagarensis Gray.) 

 A larger form than the preceding, found in similar situations. 

 Reported from the northern counties. 

 Flowers in July and August. 

 Laporte. 



