ROBINSON, — MEXICAN PLANTS, 327 
altitude 2,350 m., 28 January, 1899, no. 8057, and earlier in woods at 
base of mountains in the Valley of Mexico, Federal District, 6 November, 
1896, no. 7328. 
S. neurophylla, Ropinson & GREENMAN, n. sp. Erect strict 
slender somewhat rigid herb, 3 to 6 dm. high: stem terete, puberulent, 
simple or sparingly branched: leaves strictly opposite, thick, rigid, ap- 
pressed, linear-oblong, longitudinally ribbed with many close parallel 
nerves, 2 to 5 cm. long, 3 to 5 mm. broad, sessile by a subclasping base, 
concolorous, green and nearly glabrous upon each surface; the lowest 
shorter, the upper also much reduced and distant: heads capitately 
agsregated at the summit of the stem; bracts of the involucre rather 
rigid, glandular-puberulent, acute, 5 to 7 mm. long: corolla white, 
nearly glabrous: achene dark nearly black, hispid both between and 
upon the lighter colored angles; pappus of 4 to 6 long almost plumose 
awns and as many oblong intermediate scales. — Collected by E. W. 
Nelson between Ayusinapa and Petatlan, Guerrero, Mexico, altitude 
1,500 to 2,100 m., 14 December, 1894, no. 2133. Types in herb. Gray 
and herb. U. S. Nat. Museum. 
S. Rosei. Herbaceous smoothish perennial herb with tough dark 
fibrous roots: stems single, erect or slightly decumbent, 3 to 5 dm. high, 
usually branched from the middle, puberulent (under a lens) with 
crisped white hairs. or quite glabrate; branches opposite, ascending: 
leaves opposite, sessile, oblong or lance-oblong, subcoriaceous, veiny, 
crenate-serrate or nearly entire, usually obtuse, with 3 to 5 more or less 
anastOmosing nerves: heads in several small dense somewhat leafy- 
involucrate capitate corymbs, these together forming a very loose leafy 
corymb; involucral bracts green, linear, attenuate, very acute, 8 to 10 
mm. long, almost glabrous, not much surpassed by the white or pale 
purplish corollas: achenes black, glabrous; pappus of 3 or more oblong 
obtuse scales with or without 2 or 3 naked awns.— Collected by Dr. 
J. N. Rose on the Sierra Madre, west of Balafios, Jalisco, 15 to 17 
September, 1897, no. 2994; also in the state of Durango, 13 August, 
1897, no. 2258. This species is evidently related to S. Pringlet, but 
differs in its short-pedicelled glomerate heads, larger leaves, etc. It is 
also related to 8. venosa, Gray, and S. Plummerae, Gray, but differs 
rom both in inflorescence and character of its involucral bracts. 
S. Seleriana. Stems stoutish, lignescent, terete, white-lanate upon 
the younger internodes, soon arachnoid, glabrate, and at length verrneose 
with prominulous lenticels: leaves all opposite, decussate, petiolate, 
oblong, crenate at the sides, subentire at the acutish apex, entire at the 
