COMPOSITAE. Vo. ITI. 
4. Parthenium hispidum Raf. Creeping 
or Hairy Parthenium. Fig. 4435. 
eae teen hispidum Raf. New Fl. N. A. 2: 35. 
1836. 
P. repens Eggert, Cat. Pl. St. Louis 16. 1891. 
Similar to the two preceding species, but 
lower, seldom over 2° high. Rootstocks slen- 
der, forming runners; stem pilose or hispid 
with spreading hairs; leaves hispid on both 
sides, irregularly crenate, sometimes lyrate at 
the base, the teeth rounded and obtuse; heads 
fewer, slightly larger, in a small loose corymb; 
outer bracts of the involucre proportionately 
broader. : 
Barren rocky soil, Missouri to Kansas and 
Texas. April-July. 
56. CRASSINA Scepin, Sched. Acido Veg. 42. 1758. 
[Zinnia L. Syst. Ed. 10, 1221. 1750.] 
Annual or perennal herbs, some species shrubby, with opposite, entire, or sparingly ser- 
rate, mostly narrow and sessile leaves, and large or middle-sized heads of both tubular and 
radiate flowers. Ray-flowers pistillate, yellow, or variegated, persistent on the achene. Disk- 
flowers perfect, fertile; corolla cylindraceous, its lobes villous. Involucre campanulate to 
nearly cylindric, its bracts obtuse, dry, firm, appressed, imbricated in 3 series or more, the 
outer gradually shorter. Receptacle conic or cylindric, chaffy, the chaff subtending and 
_ enwrapping the disk-flowers. Style-branches elongated, not appendages. Achenes of the 
ray-flowers somewhat 3-angled, those of the disk flattened. Pappus of few awns or teeth. 
{In honor of Paul Crassus, an Italian botanist of the sixteenth century.] 
. ir 12 species, natives of the United States and Mexico. Type species: Chrysogonum peru- 
vianum L, 
1. Crassina grandifléra (Nutt.) Kuntze. 
Prairie Zinnia. Fig. 4436. 
Zinnia grandiflora Nutt. Trans. Am. Phil. Soc. (II) 
7: 348. 1841. 
Crassina grandiflora Kuntze, Rev. Gen. Pl. 331. 1891. 
any Uf BS 
aie mn 7 y 
x IS 
TAKE 
DWE 
Perennial, woody at the base, tufted, much : BNA 
branched, rough, 4’-6’ high. Leaves rather rigid, 
linear to linear-lanceolate, entire, 6-15” long, 
13” wide, or less, connate at the base, acute or 
acutish, crowded; heads numerous, peduncled, 
terminating the branches, 10-18” broad; rays 4 
or 5, broad, yellow, rounded, or emarginate, their 
achenes with a pappus of 2 or 4 awns; involucre 
campanulate-cylindric, 3-4” high; style-branches 
of the disk flowers subulate. 
In dry soil, Kansas and Colorado to Texas, Mexico 
and Arizona. June-Sept. 
57. HELIOPSIS Pers. Syn. 2: 473. 1807. 
Perennial herbs (a tropical species annual), with opposite petioled 3-ribbed leaves, and 
large peduncled terminal and axillary heads of tubular and radiate yellow flowers. Invo- 
lucre hemispheric or broadly campanulate, its bracts oblong or lanceolate, imbricated in 2 
or 3 series. Receptacle convex or conic, chaffy, the chaff enveloping the disk-flowers. Ray- 
flowers pistillate, fertile, the rays spreading, the tube very short, commonly persistent on 
the achene. Disk-flowers perfect, the tube short, the limb elongated, 5-toothed. Anthers 
