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facial; apex of the embryo nearly touching the base, pointing 
slightly inside of it. 
The many forms of this species may be named as follows: 
Forma GRAMINIFOLIUS (Fries), Morong. 
var. graminifolius, Fries. Novit. 36 (1828). 
This varies from the type in having delicate, flaccid, linear sub- 
merged leaves from 2 to 5 inches long and 1-3 lines wide. It is 
often found with the type and gradually runs into it. 
Forma LONGIPEDUNCULATUS (Merat), Morong. 
P. longipedunculatus, Merat, Fl. Paris. 
This I had named forma elongatus until informed by Mr. Ben- 
nett that it occurs in the work of Merat under the present name. 
It has submerged leaves 1-2 inches long and 2-3 lines wide, 
sharp-pointed, the internodes naked and extremely long, fre- 
quently as much as 10 inches. Peduncles 3-6 inches long. 
Floating leaves ovate. 
I collected this ia deep water in Lake Erie, near Buffalo, and 
Lake Seneca, N. Y. Prof. L. H. Bailey has since obtained it in 
Vermilion Lake, Minn., and Mr. F. V. Coville in Chenango River, 
An. Y. 
Forma MYRIOPHYLLUS (Robbins), Morong. 
Var. ? myriophyllus, Robbins, in A. Gray, Man. Ed. 5, р. 487 (1867). 
An interesting form with long running rootstocks which send 
up dichotomously branching and very leafy stems. Submerged 
leaves delicate, about 1 inch long by 2 lines wide, 3-5 nerved, 
linear or the upper ones oblanceolate. F loating leaves elliptical 
or lance-oblong. This form often throws up very long, naked, 
thread like stems, which bear long-petioled floating leaves, while 
the submerged leaves are on short lateral branches near the base. 
These and the “ early perishing submerged stem leaves” of which 
Robbins speaks are found only in a mill pond at Apponaug, R. I., 
the locality in which the form was first discovered, and are caused 
by the frequent variation in the depth of the water, now drained 
off and now suffered to rise. When the pond is low, the plants 
spring up and bear floating coriaceous leaves which are suddenly 
submerged by a rise in the water and very soon perish. The 
plant in order to meet the new conditions throws up proliferous 
stems which produce a new set of floating leaves. 
