458 PROCEEDINGS OF THE AMERICAN ACADEMY, 
hairs: leaves lanceolate from a narrowed auriculate base, undulate to 
sparingly and irregularly scabrous-pubescent upon both surfaces, 8 to 
5 cm. long, 8 to 11 mm. broad: peduncles slender, pubescent, 3 to 7 cm. 
long; heads often nodding, 1.2 cm. in diameter (including narrow yellow 
entire or bidentate ligules); involucre shallow, saucer-shaped, the 5 divi- 
sions united nearly to the middle, broad, scarious and ciliate at the 
margin: fruit finely striate, punctate and slightly tuberculate, bearing 
a well-developed hood surmounted by a slender recurved hispidulous 
appendage not flanked by lateral teeth at the base. — Collected by F. H. 
Lamb in sandy soil on Isla Piedra, Mazatlan, Sinaloa, 31 December, 
1894, no. 36la. Mr. Lamb’s no. 380 also from Mazatlan differs in hav- 
ing no tubercles upon the fruit and in the obsolescent appendage, yet it 
is probably of the same species. Type in herb. Gray. 
c. Pubescence copious, soft, long, villous: leaves ovate-lanceolate to ovate: aP 
.pendage of the hood short ; involucre gamophyllous only near the base. 
_? 6. M. tonerrium, Robinson. Involucre externally villous, its 
© divisions acutish.— Proc. Am. Acad. xxvii. 173 (1892). — San Luis 
han Pringle, nos. 3639, 4537. 
= Stems tending sxe oh lignescence: roots at least in del peace species 
of northern Mexico and southern United Sta 
a, Heads nee small, (including the rays) about 1 to 1.2 cm. in diameter : 
aves conspicuously sinuate or pinnatifid: rays thin, short. 
ac, 7. M. crverevm, DO. 1. c. (1836). Hood-muticous. — Laredo, Texas, 
Berlandier, who appears to have confused this with the variety ramosisst- 
mum, so that his numbers cannot be depended upon. 
Var. RAMOsIssiuum, Gray. Hood mucronate.— Syn. Fl. i. pt 2, 
239 (1884), in part. JM. ramosissimum, DC. Prodr. v. 518 (1836) ie 
Near Laredo, Berlandier, S. W. Texas and adjacent ee Palmer, 
nos. 556, 557, 558 (coll. of 1880). 
Var. ARGOPHYLLUM, Gray. Hood muticous: leaves small, tomentos? 
' upon both surfaces, canescent above, snowy white beneath. — Gray in 
Wats. Proc. Am. Acad. xviii. 104 (1883 without description). — 
Coahuila and Nuevo Leon, Palmer, no. 2068 (coll. of 1880). 
8. M. Levoantuum, Torr. & Gray, Fl. ii. 271 (1842).— The com 
monest form of our southwestern States. Kansas, Hamilton County, — 
Hitchcock, no. 250; W. Texas, Lindheimer, no. 636, Reverchon, 2% 
1380*, Thurber, no. 128, Heller, no. 1632, Pope, Bigelow, Wislizenus; 
_ New Mexico, Thurber, no. 1105, Wooton, no. 117; Arizona, “Rothrock, 
no. 327, Palmer, no. 608, Pringle, coll. of 1884; Chihuahua, Pringle. 
This plant has of late been generally regarded as a mere form 
