BULLETIN 
OF THE 
TORREY BOTANICAL CLUB 
Vol. Xll.l New York, Feb. and Mar, 1885. [Nos. 2 & 3. 
Notes on Limnanthemum lacunosum, Griseb. 
r 
By Joseph Schrenk. 
(Plate XLViii.) 
In No. 3, Vol. X., of the Bulletin (March, 1883), Miss E. G. 
Knight reported the discovery of sotiie submersed leaves in two 
specimens of Limnanthemum lacunosum, Griseb., collected in Nova 
Scotia. These leaves were "3 by 2.5 in., of a delicate texture, dia- 
phanous, and of a light green color with a tinge of red," and had " a 
broader sinus than the floating leaves." In examining some speci- 
mens of our Limnanthemum that I had taken from Squam Lake, N. 
H., in 1881 and 1882 (in the month of August), I found that the 
submersed leaves of my plants were quite different from those 
flescribed by Miss Knight. In 1883 and 1884 I gathered some more 
specimens from Squam Lake, and also some from Rockland Lake, 
N. Y., and from Bantam Lake, Conn., and found the submersed 
leaves of all the plants from these localities to agree in size and form 
with those taken from Squam Lake in previous years. 
The blades of these leaves are only from 5 to lo™"" wide and 
about lo'""^- long, and of various shapes, oval, obovate, broadly ovate, 
sometimes with truncate base, but always 7vitliout any sinus. They 
are of a bright green color, virithout the reddish tinge peculiar to the 
floating leaves. The petioles are flat and from 2.5<="'- to (f^- long. 
After having examined this interesting plant and its descriptions 
by the various authors, I venture to offer the following remarks as a 
contribution to the better understanding of its morphology and 
histology. What I especially propose to show is that the inflorescence 
IS not inserted on \ht petiole, as stated below.* 
'The latest published description of our Limnanthemutn that I could find, is 
contained in the last edition (1883) of A. W. Chapman's Flora of the bouthern 
United States, and reads thus: ^^Limnanthemum, Gmelin. Perennial aquatic 
herbs with floating, circular or cordate, spongy leaves, and white peduncled flowers 
flustered near the summit of the long petiole." In Woods Classbook of Botany we 
hnd the following: "Petioles long, bearing the flowers in an umbellate cyme 
Jelow the roundish leaf." Gray's Manual says: " Perennial aquatics, with rounded 
floating leaves on very long petioles, which, in most species, bear near their summit 
he umbel of (polygamous) flowers . . • sometimes shooting forth new leaves 
\^^ the same place, and so spreading by a sort of proliferous stolons. In Gray s 
Synopt. Flora of N. A. we find the following passages: - Lxmnantkemum 
l^f.^V'' ■ • • the flowers in our species as if umbellate-fascicled on the 
Pf^'°l^- . . . L. lacunosum, Griseb. Petioles and stolons filiform, much 
elongated: . . . umbel of flowers borne near to the base of the leaf. . . . 
.^e Candolle. Prodr ix no Sec^ ii Nymphccan the, Griseb.: " Cymoe petiohs 
■"^^"^•" Cf. also Tho"'Shan,ihe Native Flowers and Ferns of the U. S.. l., 93- 
/ 
