Tagetes sororia Standl. & Steyerm.

Tagetes nelsonii Greenman, Proc. Am. Acad. 39: 117. 1903
A tall stout annual; stem striate, purple, glabrous, 5 dm. high or more; leaves pinnate,
petioled; leaflets 3-7, lanceolate or elliptic, 1-6 cm. long, 0.5-2 cm. wide, acute, sharply and
evenly serrate, dark-green and glabrous or nearly so above, pubescent, especially on the veins
beneath, with numerous small scattered glands; heads numerous in a corymbiform compound
cyme, short-peduncled; involucre cylindric, about 8 mm. long; bracts 5-7, with deltoid tips;
glands partly elliptic and partly smaller and round, rather irregularly arranged; ray-flowers 5
or 6; ligules oblong, 5 mm. long; disk-flowers 9-12; corollas 4 mm. long, greenish-yellow;
achenes 4-5 mm. long, glabrous; squamellae linear, very unequal, the longer nearly 2 mm.
long, the shorter 0.5 mm. long.
Type locality: Tumbola, Chiapas. Distribution: Known only from the type locality.