ROBINSON AND GREENMAN.— GENUS PERYMENIUM. 527 
nolomoides), Huitzo, L. C. Smith, no. 218, Yalalag, EL. W. Nelson, 
no. 954; also on the extinct volcano of Batea, Guillemin-Tarayre, 
and (?) rocky hills near Chihuahua, Pringle, no. 152 (distrib. as 
P. parvifolium). 
b. Leaves ovate-oblong to lance-oblong, obscurely serrate to entire, distinctly paler 
and very finely pubescent or canescent-tomentulose beneath. 
18. P. croceum. Copiously branched shrub; branchlets slender, 
tetragonal, scabrous: leaves ovate- to lance-oblong, acute to attenuate, 
3-nerved, obsoletely serrate, rather abruptly narrowed at the base, 4 to 9 
cm. long, 1.3 to 1.8 em. broad, puberulent and scabrous above, very 
finely appressed-pubescent between as well as upon the veins beneath : 
heads numerous, showy, borne in the upper leaf-axils and subumbellate 
at the ends of the branches; pedicels 1.5 to 2 cm. long: involucral scales 
appressed, imbricated in 2 to 3 rows, unequal, the outer not only shorter 
but narrower, lanceolate, the inner ovate, rounded and ciliate at the 
summit: ligules about 7, oval, 8 to 10 mm. long, 6 mm. broad, yel- 
low shading into deep orange towards the base.— State of Durango, 
Dr. J. N. Rose, no. 2321; also secured by the same collector between 
Pedro Paulo and San Blascito, Tepic, no. 1991. Types in herb. U. S. 
Nat. Museum and herb. Gray. 
19, P. pexxitum, Klatt. Leaves thinnish, ovate-lanceolate, attenuate, 
entire or nearly so, drying dark, the under surface covered with a very 
fine canescent tomentum: heads 3 to many at the ends of the branches; 
pedicels sometimes very short, sometimes much elongated. — Leopoldina, 
xxiii. 143. P. discolor, Sch. Bip. ace. to Klatt, 1. c.; Hemsl. Ll. ¢., in 
part; not Schrad. — Mexico, Yavesia, Liebmann, no. 875; also moun- 
tains of Orizaba, Thomas, Botteri, no. 313, Bourgeau, no. 2927, Seaton, 
no. 125. Specimens from the Berlin Garden (1839) have elliptic obtuse 
crenate leaves. . 
20. P. piscoLor, Schrad. Shrub 3 to 5 m. high, very similar to the 
preceding species but with smaller thicker tomentulose leaves very rugose 
above, and not turning dark in drying: heads numerous; pedicels never 
much elongated. — Ind. Sem. Hort. Gotting. 1830; Linnea, v. Lit.-Ber. 
2; DC. Prodr. v. 608, excl. synon.; Hemsl. 1, c. as to plants of Oaxaca. 
— Mountains and foothills of Oaxaca, Andrieu«, no. 305, Pringle, no. 
4650, L. C. Smith, nos. 129, 820. 
= = = Heads as in the preceding group ; involucral scales not ciliated. 
a. Leaves linear-oblong, very small. 
21. P, microphyllum. Shrub with slender terete smooth gray 
