EATON: ISOETES RIPARIA CANADENSIS AND I. DopcEI 361 
“On the island above Bethlehem, Pa., bridge, growing between 
stones and gravel on the banks, always covered with water and at 
the level of the lowest stage of water in Lehigh river. E. Durand. 
Oct. 20, 1866.’ This last, being immature, will be dismissed from 
further consideration, save to state that. Engelmann (Notes and 
Sketches, §9: 93) says: “/. riparia. Cannot be Exgelmanni (and 
is probably not from Bethlehem).”’ 
The former is sketched on the same page under title of /. 
paupercula A, Br., under which name both of these appear in 
Hb. Engelm. Pencilled notes read: “ /. paupercula A. Br: in litt., 
sclerenchym cells on sporangium but very light yellow, not brown. 
Bast-bundles fully developed, only 2 (Braun says, I think I have 
seen 3 or even 4). I take it to be 7zparza after repeated investiga- 
tions which certainly show some bast-bundles in the stiff rigid 
leaves.’’ This is accompanied by the following note: “ A. Braun 
in litt., April 3, 1867. ‘/ paupercula mihi; doubtful between 
riparia and Engelmanni (as Engelmann expressed himself in send- 
ing them). A hybrid? Sporangium with pale sclerenchym cells. 
Macrospores larger, ridges erose, somewhat reticulate below, 
scarcely differing from rzparia but with 2 median bast-bundles.’”’ 
One of the first collections of /soetes in America was made by 
Moser in 1832, in Pennsylvania. A specimen of his collecting 
is in the Engelmann collection, and is referred by Engelmann to 
I. Engelmanni. It was collected on an island in the Lehigh, prob- 
ably, as Engelmann’s label reads, at Bethlehem. Although rather 
immature, this is doubtless 7, Canadensis, as spores are character- 
istic. The original label belonging to this specimen apparently 
now adorns a sheet of /. sefacea, and one written by Engelmann 
accompanies the specimen. 
Finally there is a sheet bearing specimens collected by E. A. 
Rau, August, 1882, on “shaded banks of Lehigh river, at Bethle- 
hem, Pa.” This, to judge from pencil notes, was referred alter- 
nately to J, Exgelmanni and /, Braunii, but finally included in the 
former, where it now appears. Engelmann’s notes say: “ Very 
weak bast-bundles, sporangium spotted, macrospores .47—.57 mm., 
cristate-reticulate, stomata, microspores normally .024 mm., smooth, 
white.” I find some gynospores that reach 7ooy. The andro- 
spores mounted dry, the only way in which an idea of their 
