ROBINSON AND GREENMAN.— GENUS CALEA. 21 
serrate or dentate, rarely entire (in one or more S, American species 
pinnatifid). The limits of the genus here taken are essentially those of 
Bentham & Hooker (Gen. ii. 390), and Hoffmann (in Engl. & Prantl, 
Nat. Pflanzenf. iv. Ab. d, 246), whose generic synonymy need not here 
be repeated. The @Mexican and Central American species may be sub- 
divided according to the following characters. 
Subgenus 1. LeontorHruatmum, Benth. & Hook. f. Heads very 
large (inch or more in diameter), radiate, few or solitary, long-peduncled : 
scales of the involucre few-seriate, broad, the outer often herbaceous : 
both disk- and ray-flowers yellow: scales of the pappus numerous. — 
Gen. ii. 391, Leontophthalmum, Willd. Gesellsch. Natur. Fr. Berl. Mag. 
1807, 40; HBK. Nov. Gen. & Spec. iv. t. 409. — Mostly S. American 
species, only the following known from Mexico. 
1. C. megacephala. Erect, herbaceous, 2 or 3 feet high: stem 
striate-angulate, hirsute-pubescent, leafy to the middle and terminating 
in one or (more rarely) three long naked 1-headed peduncles (often 18 
inches in length): leaves thin, ample, hirsute upon both sides, rhombic- 
ovate or with deltoid acute or obtusish coarsely dentate blade (3 to 4 
Inches long, nearly as broad) abruptly contracted at the base, then grad- 
ually attenuate into a winged entire petiole of nearly equal length; the 
lowermost leaves smaller, obovate, and with rounded apex: heads, exclu- 
‘ive of rays, 9 to 12 lines in diameter : flowers deep orange ; ray-flowers 
15 to 20, with oblong spreading ligules half inch in length: disk conical. 
— Collected by EZ. W. Nelson at Sta. Efigenia, Oaxaca, altitude 500 feet, 
te July, 1895, no. 2844, and on top of ridge back of Tonala, Chiapas, 
altitude 1,200 to 2,500 feet, 10 August, 1895, no. 2884. A plant with- 
Sut close affinities in the Mexican species of the genus, but related to 
Several of the S. American. 
Subgenus 2. Oreriza, Llav. (as gen.). Heads few or solitary, large, 
‘o 15 lines in diameter, loosely cymose or (in C. elegans) somewhat 
densely grouped at the ends of the branches: rays long (nearly or quite 
f inch in length) white or roseate: leaves sessile or nearly so. 
* Leaves oblong, narrowed at the base. 
me 0, Palmeri, Gray. Herbaceous, erect or slightly decumbent: 
“em simple or divided almost from the base, pubescent, 18 inches to 2 
feet high: leaves 2 to 3 inches long, 4 to 6 lines broad, denticulate and 
ciliated, 8-nerved: heads 1 to 9, in terminal loose cymes ; slender pedun- 
cles nearly naked; the floral leaves short and linear: involucral bracts 
green, few-seriate and more nearly equal than is usual in the genus. — 
Proc. Am. Acad. xxii. 430. —On the Rio Blanco, Jalisco, Palmer, no. 
