CATALOGUE. 169 



simple or branching toward the summit ; leaves 1-2-ternately parted, the 

 divisions spatulate or oblanceolate, obtuse, simple or lobed ; scales of the 

 involucre equal, acuminate, in 2-3 series; ray-flowers about 15 (disk-flowers 

 many) ; blade toothed or lobed ; tube of the disk-flowers externally glandu- 

 lar-hairy; achenia narrowly turbinate or clavate, black, slightly quad- 

 rangular, smooth, ribbed or striate, and longer than the corolla; pappus 

 none— Arizona (812, 609). 



Palafoxia linearis, Lag. {vide Botany of Fortieth Parallel, p. 424). — 

 Arizona. 



Palafoxia Hookeriana, T. & G. 1, probably var. subradiata, T. & Gr.— 

 6-1 2' high, simple or branched ; leaves linear or linear-lanceolate, hirsute, 

 1-1^' long; pedicels and flowers viscidly glandular-hairy; scales of invo- 

 lucre lanceolate, acute, sub 2-seried; rays variable, large or small, regularly 

 or irregularly 3 cleft; pappus (ray) reduced to small obtuse scales, half a 

 line long; achenia sub 4-angled, hairy, broadly clavate ; disk-flowers deeply 

 5-parted ; tube long and slender, or short and thick ; pappus of 5-8 lanceo- 

 late or oblong scales, which are nearlyas long as the hairy, clavate achenia. — 

 A plant which appears to be variable in almost everything about the flower 

 except the disk-achenia. Deserts of New Mexico, Loew. 



Porophyllum* macrocephalum, DC. — Annual, erect, glabrous ; lower 

 leaves linear, upper broadly oval (all petioled and glaucous) and sinuate- 

 dentate; marginal glands nearly a line long and half as wide; flowers 

 solitary, terminating the pedicels, which are hollow and dilated above; scales 

 of the involucre linear, 10" long, with one or' two lines of glands 1£" long 

 and %! wide ; achenia clavate, hairy ; pappus fulvous, rough, with delicate 

 hairs, nearly or quite as long as the slender flower-tube ; limb of the flower 

 dark brown. — A striking species, found usually on or near limestone rocks. 

 Sanoita Valley, Arizona, at 4,500 feet altitude (682). 



* Porophyllum, Vaillant. — Head several- to many-flowered, with all the flowers perfect. Involucre 

 cylindrical or cyliudraceous, of 5 to 10 oblong or linear equal scales in a single series. Receptacle small, 

 naked. Corollas with n slender or filiform tube and a narrow 5-cleft limb. Style-branches slender, 

 tipped with a subulate- filiform hispid appendage. Akenes long and slender, nearly terete, striate or 

 angled. Pappus of copious, rather rigid, scabrous, capillary bristles, about the length of the corolla. — 

 Herbs glabrous and often glaucous ; with slender branches terminated by pedunculate heads of yellow, 

 whitish, or purplish flowers, and alternate, or below, opposite leaves ; these and the scales of the involucre 

 marked by scattered immersed oil-glands, in the manner of Tagetes, &c, therefore strong-scented. — Gray, 

 Fl. Cal. 1, p. 398. 



