Family 2. CARDUACEAE 
By PER AXEL RYDBERG 
Herbs, shrubs, or rarely trees, with alternate, opposite, or verticillate leaves 
and watery juice. Flowers usually of two kinds: disk-flowers usually herma- 
phrodite, in the center of the head, and ray-flowers usually pistillate or neu- 
tral, around the periphery. Corolla of the disk-flowers usually tubular, actino- 
morphic, regular, consisting of a narrow cylindric tube, a somewhat enlarged, 
often campanulate, or turbinate throat, and a 5- or rarely 4- or 3-toothed 
limb; in a few cases the disk-corollas have an enlarged, oblique, and irregularly 
toothed limb, and in the tribe MuTisimax bilabiate with the outer (lower) lip 
elongate and 3-toothed and the inner (upper) lip short and deeply two-lobed. 
Stamens in disk-flowers isomerous; filaments distinct; anthers introrse, con- 
nate into a tube (syngenesious), basifixed, the connective usually prolonged 
into an appendage at the top, the anther-sacs often prolonged at the base (the 
anthers then said to be sagittate at the base), and the auricles sometimes pro- 
longed into a tail (caudate) ; pollen-grains globose, often echinulate. Style in 
fertile disk-flowers usually more or less deeply 2-cleft; in some cases the stig- 
matic lines extend to the very tip of the style-branches, in other cases the 
branches bear a longer or shorter sterile appendage at the end: when without 
appendages, the branches may be truncate and bearing a hair-pencil at the end 
(Senecioid style); or much elongate and acute at the end, and hispidulous on 
the outside along their whole length (Vernoniozd style) ; or less elongate, rounded 
at the end and usually less or not at all hispidulous (Jnuloid style); when elon- 
gate and acute, they may bear a ring of stronger and longer hairs below (Cyna- 
roid style); when appendages are present they may be obtuse at the apex and 
usually thicker than the stigmatic portion of the branches (Ewpatorioid style); 
or acute and tapering from the base and then either hairy on both sides (Helian- 
thoid style) or glabrous at least within (Asteroid style). Style in sterile disk- 
flowers, where the pistil is abortive, less deeply divided or entire and then the 
end either club-shaped, capitate, or (as in some species of Arfemisia) peltate 
and inverted umbrella-like as it is in AMBROSIACEAE. Corolla of the ray 
flowers most commonly ligulate, 7. e., the throat and limb cleft on one side, 
bent over to the other side into a strap-shaped or rarely cuneate organ, the 
ligule, or in MUTISIEAE and in a few genera of other tribes bilabiate, or some- 
times, especially in GNAPHALIEAE, reduced to the tube and filiform, or want- 
ing, or rarely actinomorphic like the disk-corollas. Stamens in ray-flowers 
wanting. Pistil in ray-flowers either like that of the disk-flowers or more often 
with more elongate style-branches and approaching the Vernonioid style but 
usually less hispid and more obtuse. 
If ligulate ray-flowers are present, the head is said to be radiate, and if 
they are absent, discoid; the head is said to be homogamous when all its 
VOLUME 33, Par? 1, 1922 45 
