186 TWELFTH ANNUAL REPORT. 



S. simplex, Hudson, var. Nuttallii, Gray. Bur-reed. 

 St. Croix river, Parry. 



S. simplex, Hudson, var. aiidrocladiim, Gray. Bur-reed. 

 Freeborn county, Upham. 



S. simplex, Hudson, var. angustifolium , Gray. Bur-reed. 

 Lapham. North. [Isle Royale, Whitney.] 



S. minimum, Bauhin. Bur-reed. 



Brooks, St. Croix river. Parry; lalce of the Woods, Dawson. [North of lalce Super- 

 ior, Agassiz; Isle Royale, Whitney.] North. 



NAIADACEiE. Pondweed Family. 



NAIAS,L. Naiad. 



N. flexilis, Rostk. & Schmidt. Naiad. 



Throughout the state. Blue Earth county, Leiberg; plentiful iu Martin county and 

 in Emmet county, Iowa, Cratty; Minneapolis (abundant), Miss Butler. [Manitoba, 

 Macoun.] 



ZANNICHEL.LIA, Micheli. Horned Pondweed. 



Z. paliistris, L. Horned Pondweed. 



Feat-bogs between Kasota and Mankato, Leiherg. Rare. 



POTAMOGETON, Tourn. Pondweed. Potamogeton. 



P. uataus, L. Pondweed. 



Common, or frequent, throughout the state. 



P. Claytonii, Tuckerman. Pondweed. 



Plentiful near Stewart river, north of lake Superior, Roherts. 



[P. rufescens, Schrader, will probably be found in northeastern Minnesota.] 



P. onchites,Tuckerm. Pondweed. 



Le Sueur river. Blue Earth county, Leiberg; Emmet county, Iowa (.frequent), Cratty. 

 South. 



P. amplifoliiis, Tuckerman . Pondweed. 



Plentiful in Devil's Track lake, north of lake Superior, Roberts; lake Vepia, Miss 

 Manning; Emmet county, Iowa (rare), Cratty. 



P. gramineiis, L., var. heteropliyllus, Fries. Pondweed. 



Throughout the state. Abundant in Devil's Track lake, Roberts; frequent in Emmet 

 county, Iowa, Cratty. 



P. lucens, L. Pondweed. 



Throughout the state, but infrequent. LakeMinnetonka.iJobcj-ts; White Bear lake, 

 Ramsey county, Simmons; Stearns county, Campbell. [North of lake Superior, Agassiz; 

 Manitoba, M acoun.] 



P. lucens, L., var. minor, Nolte. Pondweed. 

 Lake Minnetonka, Herricli, Roberts. 

 [P. praelongus, Wulfen., will doubtless be found in Minnesota.] 



