18 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
Dicoria calliptera Rose & Standley, sp. nov. PLaTE 12. 
Branches half a meter long or less, spreading, diffusely branched; stems very slen- 
der, finely canescent, striate; leaf blades ovate or broadly oblong, small, 5 to 14 mm. 
long and 3 to 11 mm. wide, obtuse, narrowed at the base, entire, somewhat crispate, 
rather thick, finely but not closely canescent on both surfaces, all on slender petioles 
as long as the blades; outer involucral bracts oblong to ovate, obtuse, the inner sac- 
cate, scarious, becoming 5 mm. long, sparingly glandular-viscid, the margins dentate; 
achenes | or 2, oblong, 5 mm. long and 2 mm. wide, somewhat puberulent and viscid, 
bidentate at the apex, dark brown, the wings scarious, pectinate, more than half as 
wide as the achene, straw-colored, not incurved. 
Type in the U. 8. National Herbarium, no. 574268, collected on sand hills near 
Adair Bay, Gulf of California, Sonora, November 20, 1907, by Mr. G. Sykes, (no, 63). 
This is nearest Dicoria canescens, but the fruit has much wider, not incurved wings, 
the inner bracts are much smaller, and the pubescence of the stem is all appressed and 
not spreading as in that species. 
EXPLANATION OF PLATE 12.—a, Branch of the type; 6b, staminate floret; c, fruiting head; d, outer 
involucral bracts; ¢, achene; f, inner involucral bract. a, Natural size; b, scale 12; c, scale 6; d, e, f, scale 8, 
Chrysoma laricifolia (A. Gray) Greene, Erythea 3: 11. 1895. 
Type locality, ‘‘On mountains, at Guadalupe Pass, New Mexico.” 
Hornaday Range, Pinacate Mountains, November 14, 1907, MacDougal. 
Baccharis glutinosa Pers. Syn. Pl. 2: 425. 1807. 
Type locality, ‘‘In R. Chilensis ruderatis.”’ 
Walls Well, Ajo Mountains, Arizona, November 8, 1908, MacDougal 13. 
Baccharis sarothroides A. Gray, Proc. Amer. Acad. 17: 211. 1882. 
Type locality, ‘Southern borders of California, San Diego Co., near the old Mission 
station, the boundary monument, etc.’’ 
Walls Well, Ajo Mountains, November 8, 1907, MacDougal 5. The specimens have 
heads somewhat larger than the typical form and the pappus is about twice as long as 
in specimens from southern California. 
Encelia farinosa A. Gray, Torr. in Emory, Mil. Reconn. 143. 1848. 
Type locality not given. 
This is well illustrated in a plate of the ‘Camp-Fires.”’?! The name of ‘white 
brittle-bush” is there suggested for it. 
Isocoma fruticosa Rose & Standley, sp. nov. PLATE 13. 
Low, straggling, much-branched shrub; branches stout, covered with rough, gray 
bark; leaves very thick and fleshy, resiniferous, viscid, simple or usually pinnatifid, 
the divisions coarsely filiform, alternate, divergent or directed forward, the whole leaf 
25 mm. long or less, the lateral divisions usually 2 to 4 mm. long; heads few, 3 to 5, 
clustered at the ends of the branches, all conspicuously pedicelled; involucral bracts 
oblong, obtuse, coriaceous, much imbricated; heads narrowly campanulate, 7 to 9 mm. 
high; pappus pale yellow, 6 mm. long; achenes 2 mm. long or less, sericeous. 
Type in the U. 8. National Herbarium, no. 574278, collected in MacDougal Pass 
near the Pinacate Mountains, Sonora, November 14, 1907, by Dr. D. T. MacDougal. 
The plant is nearest Isocoma tenuisecta, but differs notably in habit and the char- 
acteristics of the leaves. 
EXPLANATION OF PLATE 13.—a, Branch of type; b, involucral bract; c, head; d, floret and immature achene, 
a, Natural size; b, scale 12; c, scale 4; d, scale 8. 
Isocoma limitanea Rose & Standley, sp. nov. PuaTeE 14. 
Stout perennial; stems several from each root, simple below, corymbosely branched 
above, glabrous except about the inflorescence, there viscid, conspicuously striate; 
' Facing page 182. 
