Emory's Rockdaisy

Perityle emoryi is a widespread polyploid of diverse habitats and is often weedy. It is variable; none of the variation appears to have population significance and does not require taxonomic recognition. The range of P. emoryi appears to be gradually expanding.

Annuals (sometimes persisting), 2–60 cm (delicate or robust, stems relatively few to many, erect or spreading); puberulent to hirsute, glandular-pubescent. Leaves: petioles 3–45 mm; blades ovate, cordate, suborbiculate, or triangular, 17–60 × 10–50 mm, margins deeply toothed, lobed, cleft, or divided, lobes indented to irregularly dissected. Heads borne singly or in corymbiform arrays, 4–10 × 4–10 mm. Peduncles 1–70 mm. Involucres campanulate to hemispheric. Phyllaries 10–20, lanceolate or oblanceolate to ovate-lanceolate, 4–6 × 1–2 mm. Ray florets usually 8–14, rarely rudimentary or 0; corollas white, laminae oblong, 1–4(–6) × 1–3 mm. Disc florets 40–100+; corollas yellow, tubes 0.7–1.3 mm, throats tubular to tubular-funnelform, 0.8–1.3 mm, lobes 0.1–0.2 mm. Cypselae suboblong, oblanceolate, or subcuneate, (1.5–)2–3 mm, margins thin (not calloused), long- or short-ciliate; pappi 0 or of 1 antrorsely to retrorsely barbellate bristles 1–3 mm plus crowns of hyaline, laciniate scales. 2n = 65–72 or 100–116.

Perityle emoryi Torr. in Emory, Notes Mil. Recon. 142
1848.
Perityle nuda Torr. Pacif. R. R. Rep. 4: 100. 1857.
Perityle Emoryi nuda A. Gray, Bot. Calif. 1: 397. 1876.
Perityle californica A. Gray, Syn. Fl. N. Am. P: 32L 1884. Not P. californica Benth. 1844.
Perityle californica nuda A. Gray, Syn. Fl. N. Am. 1-: 321. 1884.
Perityle Rolhrockii Rose, Bot. Gaz. 15: 114. 1890.
Perityle Emoryi Ocruttii Rose, Bot. Gaz. 15: U7. 1890.
Laphamia nuda Benth. & Hook.; Jacks. Ind. Kew. 3: 30. 1894.
Laphamia Emoryi Benth. & Hook.; Jacks. Ind. Kew. 3: 30. 1894.
A winter annual, sparingly hirsute as w'ell as glandular-puberulent; stem branched, 1-3
dm. high; leaves petioled, the lower opposite, the upper alternate; petioles 1-3 cm. long; blades
cordate, reniform, or flabelliform, palmately lobed and incised, 1-3 cm. long; peduncles 1-3 cm. long; involucre hemispheric, 5 mm. high, 5-7 mm. broad; bracts oblanceolate, acute, glandular-puberulent; ligules about 10, white, 2-3 mm. long, 3-crenate; disk-corollas glandularpuberulent, nearly as long as the achenes; style-appendages oblong, obtuse; achenes shorthirsute on the margins, linear or linear-oblanceolate, 3 mm. long, with some deciduous hairs on the faces; pappus of a crown of small lanceolate squamellae and a single awn 2 mm. long, or bristle wanting (var. nuda).
Type locality: Cordilleras of California.
Distribution: Southern California, Arizona, Sonora, and Lower California.

Perityle grayi Rose, Bot. Gaz. 15: 118. 1890
Perityle Emoryi S.Wats. Vtoc. Am. Acad. U: \6. 1876. 'i>iot P. Emory i Tott. 1848. Perityle Fitchii Palmeri A. Gray, Syn. Fl. N. Am. 1^: 321. 1884.
A low winter annual; stem branched, sparingly hirsute and slightly glandular-puberulent above, 1-2 dm. high; leaves mostly alternate; petioles 1-3 cm. long; blades thin, sparingly pubescent, ovate in outline, 1-3 cm. long, deeply lobed with sinuately toothed lobes; peduncles 1-5 cm. long; involucre hemispheric, 5 mm. high, 7-8 mm. broad; bracts oblanceolate, acuminate, sparingly puberulent; ray-flowers about 10; ligules white, broadly rectangular, 3crenate, 2.5-3 mm. long; disk-corollas about as long as the achenes; achenes barely 2 mm. long, oblong, sometimes somewhat falcate, short-hispid on the margins; pappus of many small squamellae united into an erose crown ; awn usually wanting.
Type locality: Guadalupe Island, Lower California. Distribution: Islands of Lower California.

Perityle emoryi is a species of flowering plant in the aster family known by the common name Emory's rockdaisy. It is native to the Southwestern United States, northwest Mexico, and the Baja California Peninsula. It is a common wildflower of the deserts, and can also be found in California coastal regions.

It grows in many types of habitat, it tolerates disturbance, and it can become somewhat weedy. The plant is also known from Chile and Peru and it is an introduced species in parts of Hawaii. Its distribution is apparently expanding.