104 
Sparganium eurycarpum, LEngelm. (BUR-REED.) 
‘¢ 1823 * * my first botanical discovery * * * observed in the exten- 
sive marsh between Ipswich river and Wenham swamp; communi- 
cated to Nuttall, but it did not attract his attention” (Dr. Chas. 
Pickering, Chron. Hist. Pl., p. 1063). Common in slow waters. 
Sparganium simplex, Huds. 
“‘Outlet of Pleasant pond, Wenham, about 1860” (Dr. Chas. Pick- 
ering). 
Var. Nuttallii, Engelm. 
Foster’s pond, North Beverly. 
Var. angustifolium, Engelm. 
Merrimac river, at Lawrence; Crane’s pond, West Newbury. 
Rare. 
NATADACE. 
Notr.—This order contains many species which are very difficult to 
determine, and which require close observation of living specimens 
in order that they may be correctly placed. Mr. Charles E. Faxon, of 
Boston, who has carefully studied these plants from specimens col- 
lected in the stations mentioned below, nearly all of which he has 
himself visited, kindly revised the original list, adding many notes of 
value. 
(PONDWEED FamILy.) 
Naias flexilis, Rostk. 
Common in brooks and ponds. 
Naias Indica, var. gracillima, Braun. 
In a springy bog at Sluice pond, Lynn, 1880 (Edwin Faxon). This 
species is occasionally met with in similar places, but no other au- 
thentic specimens from Essex county have been found. 
Zannichellia palustris, L. (HornepD PONDWEED. ) 
In the brook or ‘‘upper branch” of the Mill pond above the Atlantic 
Car Works, Salem, in brackish water. 
Zostera marina, L. (EEL-GRass.) 
Everywhere in salt water, below low tide mark, along the shore. 
Ruppia maritima, L. 
In shallow, salt or brackish water, inlets, etc. Frequent. 
Potamogeton natans, L. 
Ponds and rivers. Common. 
Var. prolixus, Koch. 
In flowing water, outlet of Chebacco pond, Ipswich river, etc. 
Frequent. 


