BLAKE.— ENCELIA AND RELATED GENERA. 351 
Herbs, with alternate linear leaves and four-angled achenes, or scapose, 
with linear-lanceolate leaves ...............-. (HELIANTHELLA) 
ENCELIOPSIS (Gray) A. Nels. (Enecelia, and dys likeness).— 
Heads large, many-flowered, radiate or discoid, the rays neutral; 
flowers all yellow. Involucre hemispherical, the scales 2—3-seriate, 
subequal or graduated with the outer shorter, lanceolate to lance- 
ovate, equaling or somewhat exceeding the disk. Receptacle some- 
what convex; pales soft and scarious, with abruptly narrowed hairy 
tip, enfolding the achenes and falling with them. Rays long (1.5- 
4.5 em.) and narrow, several-nerved, pubescent on back and tube, 
entire or tridenticulate, absent in one species; disk-corollas with 
cylindric tube abruptly widened into the throat, and 5-toothed pubes- 
cent limb. Anthers sagittate at base. Style-branches bluntish, 
pubescent. Achenes of ray triquetrous, sterile, rarely maturing and 
developing thin corky wings; of disk compressed, very flat, villous 
particularly on the margins (or glabrate in one species), with blackish 
y and white cartilaginous border passing above into 2 teeth or 
awns, these connected by a fringe of short confluent squamellae, some- 
times completely united into a thick entire crown.— Scapose xerophy- 
tic perennials, with stout root and often much branched caudex, the 
short branches bearing tufts of thick oval or rhombic 3-5-nerved 
leaves, and one or several naked or 1-2-bracteate monocephalous 
secapiform peduncles. Type species Encelia nudicaulis se — Four 
species of very arid regions of the southwestern United Stat 
Distinguished from Helianthella by the generally shorter pia 
rom Encelia and Geraea by usual presence of squamellae, and from 
all three by habit. Forming a connecting link between Geraea and 
_ Helianthella, and probably having developed as an adaptation to 
desert conditions of the mountain loving genus Helianthella. 
Helianthella § Enceliopsis Gray, Proc. Am. Acad. xix. 9 (1883), & 
Syn. Fl. i. pt. 2. 283 (1884). 
Enceliopsis A. Nels. Bot. Gaz. xlvii. 432 (1909). 
* Heads discoid; plant hispid-canescent. 
1. E. nutans (Eastw.) A. Nels. Root Spends oe very 
thick (3 em.) and woody, bearing a short lignescen x from which 
proceed the 1-5 scapes and the tuft of crowded Lares: leaves oval, 
obtuse to rounded at tip, rounded at base, hispid-canescent with 
appressed hairs, 2-5 cm. long, on margined petioles 2-6 cm. long; 
scapes hispid with somewhat reflexed hairs, 1.5-2.5 dm. high, naked 
or with one or two narrow bracts; heads nodding in fruit, 24 em. 
wide, 1.5-2 em. pie scales densely hispid, lanceolate, 2-3-seriate, 
