NOTES ON THE AQUATIC PHENOGAMS OF IOWA, j^j 



2. S. androcladum (Engclm.) Moroug, Bull. To?'?'. Bot. 



Club. XV., 78 (1888)." 



S. simplex Huds. var. androcladum Engelm. in Gray's 



Man.. 5th ed., 481 (1867). 



Wats, and Coult., Gray's, Man. 6th ed., 548; Arthur, Fl. 

 Iowa. 30; Macmillan, Metas. Minn. Val., 33. 



Heads when mature about one inch in diameter, being 

 intermediate in size between the preceding and the next. 

 Ponds; rare. July, August. 



Davenport, Arthur's Fl. Iowa, No. 775; Wilton, Hitchcock. 



3. S. eury.carpum Engelm. Gray's Man., 2nd ed. ( 1852 ) . 



Wats, and Coult., Gray's Man., 6th ed., 548; Arthur, Fl. Iowa, 

 30; Hitchcock. Ames Fl. 521 ; Macmillan, Metas. Minn. Val., 33. 



Frequent throughout the state on the margin of ponds and 

 lakes, usually being found among a rank growth of grasses 

 and sedges. Mature heads of fruit are often 1 y 2 in. in diam- 

 eter. July. August. 



Emmet county. C ratty: Iowa City, Macbride; Ames, Hitch- 

 cock: Humboldt, Bessey : Hamilton county, Rolfs; Dickinson 

 county, Hitchcock: Washington and Winnebago counties, 

 Cedar Rapids, Shi??ick. 



NAIADACE.E. 



NAIAS Linn. Spec. PL, 1015 (1753). 



1. N. flexilis (' lVilld.)Bost. & Sch??iidl,F\. Sed. 384 (1824). 



Morong, Naiad. N. A., 59; Wats, and Coult., Gray's Man., 

 6th ed.. 566; Macmillan, Metas. Minn. Val., 40; Hitchcock, 

 Ames Fl.. 523; Arthur, Fl. Iowa, 30. 



A homely little plant, growing entirely under water, and 

 widely distributed throughout the northern hemisphere. Ponds 

 and slow streams. July, August. 



Lake Cairo, Bessey: Emmet county, Cratty; Story and 

 Dickinson counties, Hitchcock : Muscatine Rcpftcrt : Hancock 

 county. Sliimck. 



