344 — DESCRIPTIONS OF NEW SPECIES cone 
*, 
long and slender. Seales or sepals yellowish-white, rigid and cartilaginous, strongly ciliate, those 
which embrace the achenium subcarinate, and splitting at length in the centre down to the base; 
points of the scales abruptly terminating in narrow, bracteolate, leafy, hirsute, spreading points. 
Rays eight, about twice the length of the disk, mostly entire, the tube short and narrow. Stigmas 
of the ray long, ligulate, smooth, bifid. Achenium blackish, convex and strongly carinated on the 
back, oboval, scabrous and hairy towards the summit, without any vestige of winged margin, 
crowned by a minute cup, terminated on either side by two very small and hairy awns. Ache- 
nium falling off with the scale to which it is attached, and to each of which adheres two recepta- 
cular palea, with the stalk like rudiments of the male flowers. 
Division V.—AmBrosizz. (Decand.) 
Amprosia didentata. | | 
Has. Arkansa plains. The uppermost leaves frequently four-toothed on either side, near the 
base; male involucrum entire, six to eight flowered, with a projecting caudate segment. 
Ambrosia trifida. 
Has. Arkansa; in inundated places, 
Ambrosia * longistylis; scabrous, stem coppaieutiy) simple; leaves pinnatifid, 
segments oblong-linear, bractes entire; female flowers axillary, conglomerate, 
g styles, (about an inch;) fruit cornute, spiny at the sum- 
r toothed involucrum; the recepta- 
t; male flowers : about thirty, in a slight 
de at, paleaceous; cusps of the anthers filiform. 
Has. —e Mountains. ©. Allied to Franseria. 
a 
FRANSERIA. (Cavan.) 
7 ia * bipinnati fida; x, herbaceous, decumbent and diffusely branched, 
canescent and sericeous; leaves bipinnatifid, ultimate segments linear, short, 
obtuse and confluent; ‘male calyx ten to twelve-cleft, many-flowered.—F. Che 
missonis, 3. bipinnatisecta? Lesstnc, Decanp., Vol. V., p. 524. 
Has. Sea-coast of Upper California, (St. Barbara, St. Diego, &c. ») common. Stem diffuse, 
eae in a circle of two or three feet, solid, but not woody, brownish. Male florets about 
; fruit in clusters or racemes, very spiny and pungent, the involuerum pyramidal-ovate ; 
spines flat, often brown, or yellowish. Stigmas filiform, rather long and.acute. Anthers, (in the 
manner ~ the genus,) with filiformly acute tips. 
Franseria *pumila; 2, sericeously canescent, root creeping; stem erect; very 
low and short; leaves tripinnatifid, ultimate sezments short, linear-oblong, con- 
fluent; male calyx about five-cleft; spines of the fruit not exserted. 
