J. 2 NATURAL HISTORY BULLETIN. 



ZANNICHELLIA Linn. Spec. PL, 969 (1753). 



I, Z. PALUSTRis Linn. Spec. PI., 969 (i753)- 



Morong, Naiad., N. A. 57; Wats, and CoulL, Gray's Man., 

 6th ed., 565; Arthur, Fl. Iowa, 30; Hitchcock, Ames Fl., 

 523; Upham, Fl. Minn., 136. 



A graceful aquatic with capillary stems, sparsely branched; 

 flowering and ripening its fruit under water. Cosmopolitan. 

 Ponds, and slow streams. 



Ames, not uncommon, Hitchcock ; Muscatine, Refj^ert; 

 Storm Lake, Bcsscy. 



POTAMOGETON Linn. Spec. PL, 126 (1753). 



1. P. NATANs. Ltnn. Spec. PL, 126 (1753). 



Morong, Naid. N. A. 13; Wats, and Coult., Gray's Man., 

 6th ed., 558; Arthur, Cont. FL Iowa, III.; Macmillan, Metas. 

 Minn. VaL, 34. 



Ponds and slow-flowing streams; fruit maturing in August 

 which should be especially collected of all species of the genus. 



Lake township, Muscatine county, Rcppcrt ; Linn county, 

 SJiimek; Lake Okoboji and Fort Dodge, Hitchcock. 



2. P. AMPLiFOLius Tuck. Am.Jour. ScL, 2, VI., 225 (1848). 



Morong, Naiad. N. A., 16; Wats, and Coult., Gray's Man., 

 6th ed., 561; Upham, FL Minn., 136; Arthur, FL Iowa, 30; 

 Beal and Wheeler, Fl. Mich., 146. 



Slow flowing streams; rather rare. 



Emmet county, Cratty ; Muscatine, Rcppcrt; Spirit Lake, 

 Hitchcock; Tama County, Sirrine; Charles City, Arthur. 



3. P. NUTTALLii Ch. & Sch. Linn^ea, II., 226 (1827). 



P . pcnnsylvanicus Ch. & Sch. Linn., II., 227 (1827). 

 P. claytonii Tuck. Am. Jour. Sci. and Arts, ist Ser., 

 XLV., 38 (1843). 



Morong, Naiad. N. A., 18; Wats, and Coult , Gray's Man., 

 6th ed., 559; Beal and Wheeler, FL Mich., 145. 



