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71. Lemna Valdiviana, Phillippi—Several years since I found a 
‘Lemna in Patchouge poad, L. I., which seemed new and strange to 
me, not only from its habit,—peculiar in that it grows in tangled 
submerged masses, exactly like L. trisulca, L.—but also from the size 
shape, and grouping of the fronds. 
I secured it again this year in 
the same locality, and, as it does 
not well correspond in habit with 
any described form, I give here- 
with a wood cut of it. The fronds 
occur mostly in groups of 2, 4 or 
6, and are very small, not averaging 
over two millimetres in length, the 
groups of four usually measuring 
four m.m. in diameter. Figure 1 
gives a representation of a group 
magnified four diameters. 
The roots are very long— 
reaching over 25 times the length 
of the frond—and become curled, 
and recurved at the extremity be- 
sides, intertangling in great con- 
fusion. The extremity is provided 
with a sheath, as shown in Fig. 5. 
The roots-are nerved. The origin 
of the root from the under surface 
of the frond is shown in Fig. 2, 
(enlarged 16 diameters.) Fig. 3 
gives alongitudinal section through 
the root in the direction of A. B. 
in Fig. 2, it shows the oblique or- 
igin of the root; the sheath, which 
extend a very short distance; and 
the peculiar shape of the surfaces of the frond. Fig. 4 represents a 
transverse section of the frond in the direction of @. D. in Fig. 2. 
These drawings are made acurately from the microscope.—I have 
Some plants growing in my aquarium, which I can supply to any 
one wishing them. 
The plant corresponds exactly in size and shape to L. Valdiviana, 
(P hillippi), as figured in Hegelmaier, and is doubtless that species, 
though no mention is made either by him or by Austin, (L. Torreyt, 
Austin, Gray's Manual), of the submerged habit. I trust the figures 
will enable other observers te detect the plant. The fronds are 
very asymietrical. TB he 
We sent some of these Lemnas to Mr. Austin, who writes: “ The 
L, Torreyi you send has the fronds subovate and shorter than usual. 
two groups of the fronds I found no trace of air cavities.” Eds. 
2. Wolffia Columbiana, Karsten.—I have received sterile specimens 
= 
of a Wolffia, probably Columbiana, from Antrim, Michigan, col- 
