


58 
Spirodela, Schleid. 
polyrhiza, (L.), Schleid. (Lemna polyrhiza, L.) 
Wolffia, Horkel. 
Columbiana, Karst. 
ALISMACE 2. 
Alisma, L. ; 
Plantago, L., var. triviale, (Pursh). (var. Americanum, Gray.) 
Sagittaria, L. 
calycina, Engelm. 
var. spongiosa, Engelm. 
graminea, Michx. 
heterophylla, Pursh. 
subulata, (Pursh). (S. pusilla, Nutt.) 
variabilis, Engelm., var. angustifolia, Engelm. 
var. diversifolia, Engelm. 
var. gracilis, (Pursh), Engelm. 
var. hastata, (Pursh), Engelm. 
var. latifolia, (Willd.), Engelm. 
var. obtusa, (Willd.), Engelm. 
var. pubescens, (Muhl.), Engelm. 

nl 
NAIADACEZE. 
Triglochin, L. 
maritimum, L. 
palustre, L. 
Scheuchzeria, L. 
palustris, L. 
Potamogeton, L. 
amplifolius, Tuck. 
compressus, L. 
crispus, L. 
ome fl[uitans, Roth. (P. lonchites, Tuck.) 
gramineus, L. (Includes var. graminifolius, Fries, and var. 
heterophyllus, Fries.) 
val. maximus, Morong. 
var.(?) myriophyllus, Robbins. 
hybridus, Michx. 
lucens, L. 
natans, L. 
Oakesianus, Robbins. 
obtusifolius, Mart. & Koch. 
pauciflorus, Pursh. 


