162 



BOTANY. 



description of Mr. Watson.— Plate IV. Figure 6. A branch, natural size 

 7. A disk-flower. 8. Chaff of disk-flower. 9. Ray-flower. 10. Section 

 through receptacle. All except the branch enlarged 10-20 diameters. 



Helianthus petiolaeis, Nutt— Tall, erect, hispid; leaves scabrous 

 (lower sometimes opposite, upper alternate), ovate or ovate-lanceolate, 

 irregularly serrate-acuminate; petioles long (but variable in length); 

 peduncles terminal ; heads large ; involucral scales lanceolate or broadly 

 lanceolate, acute; disk-corolla hairy at base; achenia villous; pappus of 

 "two chaffy awns"; rays large, over an inch long. — Southern Arizona, 

 Nevada, and Colorado. 



Helianthus annuus, L. {Helianthus lenticular is, Dougl., see Gray, 

 Fl. Cal. 1, p. 353; also H. lenticularis, Dougl. vol. v, King's Report, and 

 Preliminary Report of Mr. Watson in Wheeler's Survey, Washington, 

 1874.) — Utah and Colorado. 



Helianthus Nuttallii, T. & Gr. — Nevada and San Luis Valley, Colo- 

 rado, with broader leaves (548). 



Helianthus giganteus, L., var. Utahknsis, Eaton — Utah. 



Helianthella unifloea, T. & Gr. — South Park, Colorado (546). 



Actinomekis* Weightii, Cray (PI. Fendl. p. 85). — Erect, somewhat 

 branching ; stems canescently hispid ; leaves sessile or slightly decurrent, 

 lower opposite, upper alternate, oblong or lance-ovate, irregularly and 

 strongly serrate, thick, scabrous, and distinctly veined, especially beneath; 

 heads on naked peduncles (6-12' long), medium-sized; scales of the invo- 

 lucre in 2-4 series, with a short stout pubescence, outer ones shorter, 

 oblong and obtuse, inner lanceolate and acute ; rays short, entire or 

 slightly toothed (or sometimes none). Achenia of the disk cuneate-oblong, 

 with a distinct wing extending half-way down the achenium on either side, 



* Actinomeris, Nutt. — Heads heterogamous, radiate ; flowers of the ray neutral and in a single 

 series ; disk-flowers hermaphrodite, fertile ; heads sometimes, by the deficiency of the rays, homogamous. 

 Involucre hemispherical or campanulate ; bracts 2-3-seried,' unequal, short or the outer ones elongated 

 and foliaceous. Eeceptacle convex or at length conical, covered with chaff, which embraces the disk- 

 flowers. Ray-corollas lignlate, spreading, entire or 2-3-toothed ; disk-flowers regular, with a short tube; 

 limb elongated-cylindrical, 5-cleft at top. Anthers entire at base. Branches of the style in the disk- 

 flowers terminated by acute appendages. Achenia laterally compressed, with margins attenuated and 

 distinctly winged. Pappus usually of two persistent awns.— Scabrous herbs. Leaves opposite or 

 alternate, petioled, sessile, or decurrent. Heads middle-sized, solitary, and with long peduncles or 

 corymbose-paniculate. — Bekth. & Hook. 



