410 RYDBERG: SOME SENECIOID GENERA—II 
rpemted different habit, but one species, Cacalia decomposita 
A. Gray, has the habit of the true Odontotrichum but the style 
of the other group. 
As constituted in this paper the genus has the following 
characters distinguishing it from Senecio: Head always discoid; 
disc-corollas white or nearly so, the tube long and slender, the 
dilation into a distinct throat obsolete, so that the corolla is 
split clear to the tube, the lobes being long and linear; the achenes 
are elliptic in cross-section, 10-15-ribbed, obovoid, rounded 
above and tapering at the base; basal leaves long-petioled, 
strongly reticulate, firm; pappus scabrous or barbellate, in one 
species wanting.. 
Leaves twice to four times pinnatifid into linear divi- 
sions. 
Style-branches somewhat flattened, obtuse, and 
slightly clavate at the tip; bracts 8-15. 
Leaves of the branches of the inflorescence not 
conspicuously foliaceous; rachis of the primary 
eee of the leaves 3-4 mm. wide; bracts 
Bee ee Wy a oe uk I. O. cirstifolium. 
feos of the branches of the inflorescence con- 
spicuous, foliaceous; rachis of the primary 
ee of the haces 5-Io mm. wide; bracts 
phe tas CREE Se oa See, Sere a ern gem 2. O. bipinnatifidum. 
Style-branches truncate at the — with a distinct 
hair-brush; bracts 5 or 
Basal leaf-blades 2-3 dm. ae stem 5-10 dm. 
Sm leafy; inflorescence ample; achenes glab- 
Sk foe aa Ee aera aa ae oe 3. O. decompositum. 
Basal ia 6 cm. long or less; stem 4-5 dm. 
high, subscapiform; inflorescence small; achenes 
WN Gea a 4. O. filicifoluum. 
Leaves not twice —— at most deeply divided; 
divisions not lin 
Leaves pinnately oe 
Plant tall, 4 dm. high or more; heads corymbose 
or panicula 
Leaf- Redes divided more than half-way to the 
mid-rib. 
Divisions of the lower leaves 5-11, parlegé 
ib rounded sinuses, again lobed o 
thed, not acuminate. 
Sexes 12-18 mm. high; bracts 8-15; 
pie: 40-50-flowered; achenes pubes- 
Sie ne leaves glabrous; bracts ovate.. 5. O. platylepis. 
