Tetracarpum flavum

Tetracarpum flavum Rydberg, sp. nov
A slender annual; stem about 3 dm. high, sparingly glandular-puberulent ; leaves alternate, 2-4 dm. long, pinnatifid into 3-5 narrowly linear divisions or the upper entire, conspicuously punctate, glabrate; peduncles 2-4 cm. long; involucre 6-7 mm. high, 5-6 mm. broad; bracts about 5, obovate, punctate and minutely puberulent, keeled, with light-yellow margins and tip; ligule 2-3 mm. long, oblong, light-yellow; disk-flowers 4-6; corollas 3 mm. long; achenes elongate, obpyramidal, 5 mm. long, densely villous-hirsute on the angles, sUghtly so on the striate faces; squamellae unequal, those of the angles lanceolate, aristate, fully as long as the corollas, the intermediate ones about half as long and acute.
Type collected in Sierra de San Felipe, Oaxaca, October 10, 1894, Charles L. Smith 263 b' 626 (herb. N. Y. Bot. Gard.).