rather shorter wool, so that they separate readily when they fall away; the
4 or 5 sterile corollas naked, connected by the crisped woolly hairs which
grow on the dilated limb.
62. DIAPERIA. Nutt, in trans. Amer. phil. soc. (n. ser.) 7. p. 337.
Heads fusiform-oblong, disposed in sessile glomerules of 4-5 together,
which are collected in large capitate and bracteate compound clusters terminating
the stem or simple and mostly proliferous branches ; the fertile flowers
8-12, pistillate, in the axils of the chaff of the receptacle, with a much
attenuated filiform truncate corolla ; the 2-3 central staminate, with a tubu-
lar-infundibuliform minutely 4-toothed corolla, destitute of ovaries, each
supported by a filiform stipe and enclosed in a chaff of the receptacle. Scales
of the involucre and the chaff of the small convex receptacle scarious, oval,,
broad and large for the size of the head, closely and somewhat distichously
imbricated and wrapped around each other, the inner successively longer ;
the 2-3 innermost chartaceous, attenuate at the base, woolly towards the
apex, each convolute and separately enclosing a sterile flower. Style in the
sterile flowers undivided ; in the fertile with 2 filiform branches. Achenia
obovoid-oblong, obcompressed, glabrous, destitute of pappus.—A small annual
erect woolly herb, with spatulate-oblong or linear-spatulate numerous
sessile entire leaves; the stems simple or often branched from the base, terminated
by the large irregularly involucrate compound head; from which
arise 1 to 5 or 6 simple branches, terminated by simple but usually smaller
compound heads, in the manner of the Herba impia ; and these rarely again
proliferous. Proper heads and primary clusters more or less bracteate.
D. proliféra. (Nutt. ! 1. c.)—Evax proliféra, Nutt. ! in DC. prodr. 5-
p. 459.
Banks of Red River, Arkansas, NuttalL ! Dr. Leavenworth ! June-Aug.—
Stems stout, rigid, 2-5 inches high, terminated by a capitate cluster one-
half to three-fourths of an inch in diameter, including a large number of small
heads: some of the branches when numerous often arising below this compound
head. Scales of the involucre few, entirely similar to the chaff, and
passing into the latter, but shorter, and woolly externally : the chaff of the
fertile flowers glabrous or slightly tomentose-ciliate : that of the sterile longest
and more rigid, much longer than the slender corolla it encloses ; the filiform
stipe of the latter fully half its own length.
63. MICROPUS. Linn.; Geertn.fr. t. 164; Schlcuhr, handb. t. 267.
Heads collected in axillary sessile clusters, several-flowered ; the fertile
flowers 5-7, in a single series, pistillate, with a filiform corolla, enclosed in
the inner scales of the involucre; the 3—7 central staminate, with an infundi-
buliform 5-toothed corolla, naked, destitute of ovaries. Receptacle small and
flat. Involucre in 2 series, each of 5-7 scales ; the exterior scarious, flattish,
spreading, bracteiform ; the interior (perhaps rather to be considered chaff of
the receptacle, as described by Nuttall) infolded and laterally compressed,
boat-shaped and very gibbous, enclosing the fertile flowers, and forming a
permanent cartilaginous covering to the smooth obovate and gibbous compressed
achenia. Pappus none.—Low woolly herbs with the aspect of
Filago or Gnaphalium.
§ Fructiferous scales of the involucre not echinate, woolly when young.—
Bombycilsena, DC.
.1 • M. Californicus (Fisch. <fc Meyer) : clusters lateral and terminal;
fructiferous scales compressed-navicular, semi-obcordate; the inner margin
straight, terminated by an erect mucronifbrm appendage with a scarious
apex— Fisch. Sf Meyer, ind. sem. St. Petersb. 1835, p. 42; DC. prodr. 7.
(mant.) p. 283.
/?. angustifolia: slender ; leaves linear, acute; heads very woolly when
young ; exterior or bracteate involucral scales oval, concaVe, scarious with a
linear green centre.—M. (Rhyncholepis) angustifolius, Nutt.! in trans. Amer.
phil. soc. 1. c.
California at Bodega, Fischer Sf Meyer. (3. St. Barbara, Nuttall!—Said to
resemble M. erectus, but the heads with a more scattered and shorter wool;
while Mr. Nuttall’s plant is more slender than that species, the young heads
with a longer wool; but the fruit See. exactly corresponding to the character
of the Russian botanists, who do not notice the leaves, &c. Perhaps there are
two nearly allied Californian species.
64. PSILOCARPHUS. Nutt, in trans. Amer. phil. soc, (n. ser.) 7. p. 340.
Heads solitary or clustered, many-flowered; the fertile flowers 8-30 in
several series, pistillate, with a filiform corolla, each enclosed in an involute
involucral scale or chaff of the receptacle ; the 5-8 central staminate, with a
dilated infundibuliform 4—5-toothed corolla, destitute of ovaries, naked. Receptacle
subglobose ; the chaff and similar, involucral scales (as the outermost
may be deemed) membranaceous, woolly, reticulated, infolded, and cucul-
late, forming thin obovoid or somewhat gibbous loose coverings to the very
smooth oblong terete or slightly compressed achenia. Branches of the style
short and filiform, in the sterile flowers minutely hairy. Pappus none.__
Very small diffusely branched and depressed woolly annuals, with the aspect
of Evax, &c. (natives of the western coast of America); with linear or
spatulate-oblong entire and sessile leaves, which are alternate, and irregularly
involucrate around the terminal or lateral sessile heads or clusters.
i ./ uLicxii. j cawui uiai, aimoupii
he mentions a beak or uncmate tips to the fructiferous chaff in some species, he has
not alluded to the true structure of this inconspicuous appendage, which in fact
exists in all the species. It consists of a small hyaline scale, forming the organic
apex of the fruit-enclosing chaff, and, as it were,: articulated with it at the summit of
t , antenor fissure: at first it is erect or spreading; but after impregnation it is more
or less inflexed, covering the fissure like an operculum. In P. tenellus, this scale is
broad, ovate, and nearly as large as the chaff itself at the time of impregnation - in
c VreSanus 11 Is similar m form, and in the full-grown chaff about half the length
of the fissure ; m P. globiferus and the nearly allied P. brevissimus, it is smaller
- proportion to the chaff, ovate-oblong, and apparently somewhat deciduous.
1. P. globiferus (Nu tt.1 1. c .): very woolly, decumbent, much branched;
von. u.—34