ROBINSON AND GREENMAN. — GENUS CALEA. 25 
above, densely tomentose and canescent beneath, 14 to 2 inches in 
diameter: heads very short-pedicelled or subsessile: scales of the pappus 
obtuse or rounded at the summit. — Oaxaca, Sierra de San Felipe, 
altitude 6,000 feet, 7 September, 1894, Pringle, no. 5784; dry hills in 
the Valley of Oaxaca, altitude 5,100 to 5,800 feet, 8 September, 1894, 
£. W. Nelson, no. 1217, and in neighboring locality without date, Velson, 
no. 1192; also in Valley of Etla, September, 1895, Alvarez, (L. C. 
Smith’s) no. 766. 
= = Involucre nearly or quite naked, without subtending herbaceous bractlets, 
or these small and scattered, lanceolate or subulate. 
a. Leaves wholly glabrous, quite smooth and free from resinous dots or globules. 
12. C. Nelsonii. Glabrous, copiously branched and very leafy: 
leaves rhombic-ovate, coarsely and rather bluntly toothed, 3-nerved, 
short-petioled, paler beneath, quite smooth but scarcely or not at all lucid 
upon both sides, 14 to 2 inches long, half as broad: heads very numerous 
in many terminal or subterminal close cymes, together forming a con- 
siderable pyramidal inflorescence : involucral bracts light colored, striated, 
obtuse : disk-flowers about 7 ; ray-flowers 2 or 3, with very short obscure 
ligules : pappus of about 12 scales. — Collected by 2. W. Nelson on the 
top of ridge back of Tonala, Chiapas, altitude 1,200 to 2,500 feet, 10 
August, 1895, no. 2887. 
b. Leaves pubescent, or at least covered on the lower surface with resinous atoms. 
) 13. C. Zacatechichi, Schlecht. Much branched shrub with harsh 
scabrous foliage: leaves rhombic-ovate to ovate-oblong, short-petioled, 
described as deeply crenate, but more often serrate-dentate, acute, cune- 
ate at the base: heads about 12-flowered, very short-pedicelled or ses- 
_ Sile in numerous small terminal cymes: scales of the involucre with 
_ Scarious and undulate margins. — Linnea, ix. 589; DC. Prodr. v.. 
672; Hoffm. in Engl. & Prantl, Nat. Pflanzenf. iv. Ab. 5, 246, f. 120, 
A-C.— On hills near Hacienda de la Laguna and Jalapa, Schiede ; 
Mirador, Sartorius ; Orizaba, Botter’, nos. 481, 488; San Pedro Sula, 
Dept. Sta. Barbara, Honduras, Thieme (no. 5300 of Donnell Smith’s 
Sets, a form approaching var. macrophylla), and Guanagaza, Dept. Sta. 
Rosa, Guatemala, Heyde & Lux (no. 6159 of same sets). The leaves 
“re reputed a remedy for cholera. A form probably of the same spe- 
cles, but having the involucral bracts less scarious-undulate and more 
often ciliolate, has been collected on hills near Guadalajara, by Palmer, 
no. 352, and Pringle, no. 2475. Another form collected by Pringle in 
the Sierra Madre near Monterey, Nuevo Leon, no. 2224, differs only in 
