GREENMAN — MEXICAN PLANTS, 307 
broadly ovate or ovate-oblong, 9 to 11 mm. long, nearly as broad, convex 
on one surface, flat on the other with a short ridge near the base. — Col- 
lected by streams, Valley of Mexico, 10 October, 1896, no. 6226. 
Stevia clinopodioides. An herbaceous perennial: roots fibrous, 
clustered at the base of the stem: stems simple or nearly so, about 30 cm. 
high, giving off at the base several slender horizontal subterranean 
root-stocks, closely pubescent above and purple: leaves opposite below, 
alternate above, spatulate, 24 to 4 em. long, 6 to 10 mm. broad, obtuse 
at the apex, gradually narrowed below to the subpetiolate base, callously 
serrate along the upper half, entire below, appressed-puberulent on the 
Veins and on the upper surface near the margin, glandular-punctate : in- 
florescence a compact dense umbel terminating the stems: heads about 
l cm. long, 5-flowered ; involucral scales linear-acuminate, often slightly 
unequal, appressed-puberulent on the outer surface, greenish purple, 6 to 
7 mm. ong: flowers considerably exceeding the involucre: corolla with 
a slender greenish tube below, ampliated above, the upper ampliated 
portion and: the limb purple; pappus paleaceous, short, exaristate : 
achenes glabrous, 3 to 4 mm. long. — Collected by C. G. Pringle, on the 
Serrania de Ajusco, altitude 3,000 m., 22 October, 1896, no. 6594. 
Stevia diffusa. Annual: roots fibrous: stems herbaceous, erect, te- 
rete, greenish purple, hirsutish pubescent with jointed hairs, interspersed 
above with a stipitate glandular pubescence: leaves (including the petiole) 
3 to7 em. long, 1 to 4 cm. broad, opposite below, becoming alternate above, 
membranous, broadly ovate to ovate-lanceolate (the uppermost often 
acuminate), acute at the apex, contracted below into a narrowly winged 
and ciliated petiole, crenate-serrate, or the more reduced leaves with a 
subentire margin, essentially glabrous upon either surface, except on 
the veins, where they are sparingly hirtellous: heads widely separated 
on long slender glandular pedicels, the latter from 1 to 14 cm. long; 
scales of the involucre 5, linear, acuminate, 6 mm. long, rather strongly 
2-nerved, the outer surface appressed-puberulent, very rarely glandular: 
flowers one third longer than the involucre: - corolla discolorous, tube 
purplish, puberulent, limb white: achenes puberulent, 3 mm. long: pap- 
pus paleaceous and 3-aristate. — Collected by C. G. Pringle, on lava beds 
hear Cuernavaca, altitude 2,100 m., 3 November, 1896, no. 6608. Per- 
haps related to S. micrantha, Lag., but with longer corollas, shorter 
achenes, and a much more diffuse habit. 
Stevia TRACHELIOIES, DC. It is interesting to note that Mr. 
Pringle has rediscovered this apparently rare species on the Serrania 
de Ajusco, altitude 3,000 m., 22 October, 1896, no. 6593, where specimens 
