360 Eaton: ISOETES RIPARIA CANADENSIS AND I. DODGEI 
of collecting account for their appearance. The spores are like 
those of Kingston plants. 
The only representative of the Cornish locality is a single small 
specimen attached to an exchange label of D. C. Eaton. It was 
collected in 1859, but the month is not stated. It is also very 
immature, and grew under water. Engelmann says of this: ‘‘ The 
whole’plant looks exactly like the Kennebunk plant which I have re- 
ferred to Engelmanni borealis, or perhaps to Tuckermannti, but spores 
differ. Dec. 25th, 1866.’’ Later this was crossed out and “‘ 77parta 
var. Canadensis” substituted. The same sheet also bears the 
legend: ‘ No doubt Braunii : =the Canada plant, Jan. 11, 1867.” 
The Kennebunk plant referred to is a single small immature plant 
from the Gray Herbarium, 1867, collector and date not given. 
The label also bears the name “ 77favia forma minor)borealis.”’ 
In the Gray Herbarium is a specimen from Kennebunk, whose 
label Mr. Fernald has kindly copied as follows: ‘“ /soetes Engel- 
manni Br., forma minor borealis. Sporis majoribus. Kennebunk. 
One of the doubtful (perhaps transitional) forms, Will examine 
again. G. E. 1867.” Mr. Fernald conjectures that this was col- 
lected by Engelmann himself, but this cannot be, as his specimen 
is given as “ Ex. Hb. Gray.” 
This completes the list of localities as recognized by Engel- 
mann, but a study of his /. riparia from the banks of the Connec- 
ticut river, opposite Brattleboro, Vt., Chesterfield or Hinsdale, N.H., 
shows it to be a more nearly mature form of /. riparia Canadensis, 
although the leaves are covered with confervae and diatoms and 
soak out so badly that I could not be sure of the bast-bundles. 
In his “ Notes and Sketches,” 59: 89, Engelmann says : ‘ Crests / 
of macrospores short, often scarcely anastomosing : (apparently 
/. Braunit), in others (especially below) almost reticulated ; very 
pale brown sclerenchym cells in sporangium. Macrospores those 
of riparia without doubt,” and again : “ Why not rather /acustris ?” 
I find among Engelmann’s /. riparia a sheet whose label bears 
this legend: “These from the banks of the Lehigh river, on an 
island near Bethlehem, growing like the Delaware riparia, in the 
sandy mud of the river, among and between stones, July 30, 
1866. E. Durand.” This is supplemented by another specimen 
which Engelmann calls “ forma parvula,” the label of which reads : 
