quinately verticillate, or often somewhat scattered; the lower ones pinnately
parted, with few and very slender capillary segments; floral leaves linear,
pectinately toothed or pinnatifid-serrate ; petals oblong; carpels strongly
2-ridged on the back, the ridges tuberculate.—Michx.! Jl. 2. p. 190 ; Ell.
1. c .; DC. prodr. 3. p. 69. Potamogeton pinnatum, W a lt.! Car. p. 56.
In shallow ponds &c. throughout the Southern and Western States!
April-July.—Stems 6-12 inches high. Bracteoles ovate, serrulate. Lobes
of the calyx very small, triangular-lanceolate. Petals mostly mucronate.
Stamens 4 (6, Elliott): anthers oblong. Stigmas linear, beset with long
purple hairs. Carpels cohering at the axis; the tuberculate ridges prominent
in the mature fruit, the re-entering angles well defined; the sides smooth
and even, or minutely scabrous.
5. M. hippuroides (Nutt.! mss.): leaves quatemately verticillate; the
lower ones pinnately parted, with capillary segments; floral leaves linear,
remotely denticulate or serrate; petals obovate; carpels nearly even, slightly
2-ridged on the back.—M. scabratum, Cham. Schlecht. in Linneea, 4.
p . 506.
Oregon, in ponds of the Wahlamet, Nuttall! California, near St. Francisco,
Chamisso (without fruit).—Appears nearly to resemble the preceding ;
but the fruit is very different.
§ 3. Flowers tetrandrous : petals somewhat persistent: carpels not ridged on
the hack: leaves alternate, or almost wanting: terrestrial or aquatic.—
Ptilophylium, Nutt. (Purshia, Raf. Hylas, Bigelow.)
6. M. ambiguum (Nutt.) : submersed leaves pinnately parted into (about
10) much attenuated capillary segments ; the" scarcely emersed ones pectinate
; the upper floral ones linear, tapering into a short petiole, sparingly
incised or toothed, sometimes entire; flowers mostly perfect; petals oblong;
carpels smooth and even (minute), slightly coherent.
a. natans: stems floating; emersed leaves as in var. y . ; the floating ones
capillary.—DC.! prodr. 3. p. 70. M. (Ptilophylium) ambiguum, Nutt.!
gen. 2. p. 212.
0. capillaceum: leaves all immersed and capillary.—M. capillaceum,
Torr.! convpend.
y. limosum (Nutt.): small; stems procumbent and rooting; leaves all linear
(rigid), sparingly toothed or lobed, often entire.—Nutt.! 1. c.; DC. 1. c.
M. procumbens, Bigel. Jl. Bost. ed. 2. p. 346. Purshia humilis, Raf. in
New York, med. rep. 2. p. 361, fide icon. ined.. Hylas pinnatus, Bigel.
ined. fide Hook.
In ponds and ditches (a. & 0.) and in wet miry places ( y .) Massachusetts !
and Long Island, New York ! to New Jersey ! and Pennsylvania ! July-
Aug.—Stems much branched (in y . 2 - 6 inches long) : the leaves scattered.
Flowers minute. Petals (calyx, Nutt.) persistent, purplish. Anthers
oblong. Stigmas penicillate.—Varies greatly in appearance, according to
the situation in which it grows.
7. M. tenellum (Bigel.): stems (scapes) almost leafless, simple, arising
from a prostrate rhizoma; floral leaves or bracts minute, entire ; flowers
(6-15, monoecious) alternate; petals linear-oblong; carpels smooth and even.
—Bigel.! Jl. Bost. ed. 2. p. 346 ; DC. ! 1. c .; Hook. ! Jl. Bor.-Am. 1. p.
216. M. nudum, LaPylaie! ined. Hylas aphyllus, Bigel. ined.
Borders of ponds, Newfoundland, La Pylaie ! New England States ! and
Northern part of New York! July,—Scapes slender, 4-10 inches high,
with numerous scale-like rudiments of leaves, often 4-6 from the same
slerjder rhizoma, of which several are infertile. Floral leaves a little longer
than the purplish flowers. Anthers oblong. Stigmas penicillate.—We have
beautiful specimens from Mr. Oakes and Mr. Tuckerman, but the ripe fruit
is wanting.
15. HIPPURIS. Lin n .; Gcertn.fr. t. 84 ; Juss. in ann. mus. 3, t. 30, f . 3.
Calyx with a minute entire limh. Petals none. Stamen 1, inserted on
the margin of the calyx. Style filiform, stigmatic the whole length, received
into a groove of the stamen. Fruit cartilaginous, 1-celled, 1-seeded. Seed
pendulous.—Aquatic perennial herbs, with simple stems, verticillate entire
leaves, and axillary minute flowers,'which are often polygamous.—Horse-tail.
1. H. vulgaris (Linn.): leaves in whorls of 8-12, linear, acute, sphacelate
at the apex. Hook.—Linn. spec. 1. p. 4 ; Engl. hot. t. 763 ; Michx. !
Jl. 1. p. 1 ,• Torr.! Jl. 1. p. 2 ; Hook. ! Jl. Bor.-Am. 1. p. 217.
0. lower leaves much longer, membranaceous, not sphacelate at the apex.
Hook. 1. c.
In ponds and borders of lakes, Labrador! Greenland, and Subarctic
America! Sitcha and N. AY. Coast, to New York! and Pennsylvania?—
Stem a foot or more high.—This plant is very uncommon in the United
States, and is only found in the more northern portions. The plant so called
in the late Mr. Drummond’s collection, from Quaker Bridge, New Jersey
(Compan. to hot. mag. 1. p. 46), which it was thought might prove a distinct
species, is Sclerolepis verticillata (Sparganophorus, Michx.), without flowers,
in which case it often much resembles Hippuris.
2. H. marilimd (Hellen.) : leaves 4-6 in a whorl, lanceolate, obtuse, not
sphacelate at the apex. Hook.—Hellenius, diss. Hipp. (1786); FI. Dan. t.
1261 ; Reichenb. ic. bot. t. 86, ƒ. 182; DC. 1. c. ; Hook. 1. c. H. tetra-
phylla, Linn. f. suppl. p. 8 1 ; Richards, appx. Frankl. journ. ed. 2. p. 2.
Subarctic America from Labrador to Kotzebue’s Sound.—Probably too
near H. vulgaris.
3. H. montana (Ledeb.): very small and slender; leaves about 6 in a
whorl, linear, acute.—Ledeb. in Reichenb. 1. c. f . 181 ; Cham, Schlecht.
in Linneea, 4. p. 507 ; DC. 1. c.
Turfy places, Unalaschka, Eschscholtz! Chamisso.—The plant has quite
the habit of a small Galium.
Or d e r LVII. LOASACEiE. Juss.
Sepals united into an equally 5-lobed calyx, persistent. Petals 5,
sometimes 10, the inner series (transformed stamens ?) mostly dissimilar
or smaller, inserted in the throat of the calyx. Stamens
numerous, rarely few or definite, inserted with the petals ; a portion
of the outer filaments often dilated or petaloid and mostly sterile ;
the others commonly disposed in fascicles opposite the petals and
slightly u n ite d : anthers innate or adnate. Ovary coherent with
the tube of the calyx, I-celled, with mostly 3 parietal p lac en ta , “ or
with 1 free central lobed one” (Lindl.) : ovules numerous, or some