A. PALMERI. 155 



ECOLOGY AND USES. 

 Artemisia pygmaea is a dwarf shrub with greatly reduced leaves, corresponding with 

 its climatic position and its habitat in alkaline areas, where it is associated with the 

 halophytic Chrysotha-pinus nauseosus consimilis. Its small size and rare occurrence 

 preclude any uses. 



29. ARTEMISIA PALMERI Gray, Proc. Am. Acad. 11:79, 1876. Plate 23. 

 Tall Sagebrush. 



A shrub 12 to 30 dm. high, with straight, wand-like herbaceous stems that commonly 

 make clusters about 10 dm. across, the habit then similar to that of A. ahrotanum, or 

 sometimes in younger plants the stems few or solitary, nearly simple, and more her- 

 baceous, the odor strong, but not unpleasant; flowering stems erect, conspicuously 

 striate, glabrous or minutely puberulent, reddish; principal leaves petioled or sessile by 

 a narrow base,5 to 15 cm. long, pinnately parted into 3 to 5 long linear lobes with closely 

 revolute margins or entire and linear, green and glabrous or minutely puberulent above, 

 densely white-tomentose beneath; upper leaves similar but more of them entire, nearly 

 wanting in the inflorescence; inflorescence an open terminal pyramidal panicle, 15 to 40 

 cm. long, 3 to 10 cm. broad; heads homogamous, on peduncles 1 to 5 mm. long or some- 

 times sessile, mostly nodding at maturity; involucre hemispheric, 3 to 4 mm. high, 

 2 to 3.5 mm. broad; bracts 7 to 12 (and in addition 10 to 20 elliptic obtuse bracts scat- 

 tered among the flowers), ovate, acutish, the outer ones but little shorter than the inner, 

 sparingly pubescent or glabrous, scarious-margined ; ray-flowers wanting; disk-flowers 

 12 to 25 or rarely up to 35, fertile, corolla narrowly funnelform or nearly tubular, 5- 

 toothed, 1.5 to 2.2 mm. long, glandular-granuliferous especially on the tube; style- 

 branches flat, truncate and erose at summit (sometimes described as included but 

 long-exserted and coiled at maturity in most specimens) ; achenes nearly prismatic but 

 slightly narrowed below, 4-angled, the summit truncate, granuliferous. 



Southwestern San Diego County, California and northern Lower California. Type 

 locaUty, San Diego County, California, in Jamul Valley, 20 miles east of San Diego. 

 Collections: Type collection, 1875, Palmer (Gr, NY as No. 193); near San Diego, 1899, 

 Purpus (UC, Phila); same locality, September 9, 1899, Brandegee (Pomona College 

 Hb.); near National City, Brandegee (UC, US); Oneonta, San Diego County, July, 1900, 

 Brandegee (Phila); Alpine, San Diego County, August 6, 1894, M earns 3942 (US); bluffs 

 near the sea. La JoUa, Ahrams 4013 (DS, Gr, NY); All Saints Bay, Lower California, 

 July, 1882, Fish (Gr). 



SYNONYM. 



1. Artemisiastrum PALMERI Rydbefg, N. Am. Fl. 34:285, 1916. — A. palmeri. 

 RELATIONSHIPS. 



The relationships of this species are exceptionally obscure. The presence of chaff on 

 the receptacle is not known elsewhere in Artemisia and it was principally because of this 

 that Rydberg recently set the species aside as a new genus, namely, Artemisiastrum (N. 

 Am. Fl. 34:285, 1916). The objections to this treatment have been stated earlier in this 

 paper (p. 33). Aside from this character, A. palmeri plainly goes into the section Seri- 

 p/iiditzTO, although it differs from all of the other members of this section in several details. 

 No other American species has such elongated herbaceous branches, although true herbs 

 are common among Old World species; the cut of the leaf and the peduncled heads are 

 more suggestive of A. dracunculus or of certain forms of A. vulgaris than of any member 

 of the section Seriphidium; and the involucral bracts are more nearly equal in size than 

 in other species, while at the same time their number is greatly reduced. It is possible 

 that some of the bracts on the outer part of the disk are in reality bracts of the involucre 

 which have taken up a more central position, but the number is sometimes too great to 



