ROBINSON AND GREENMAN. — GENUS PERYMENIUM. 527 



nolomoides), Huitzo, L. C. Smith, no. 218, Yalalag, E. W. Nelson, 

 no. 954; also on the extinct volcano of Batea, Gioillemin-Tarayre, 

 and (?) rocky bills near Chihuahua, Prlngle, no. 152 (distrib. as 

 P. parmfolium) . 



b. Leaves ovate-oblong to lance-oblong, obscurely serrate to entire, distinctly paler 

 and very finely pubescent or canescent-tomentulose beneatli. 



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 cm. broad, puberulent and scabrous above, very 

 finely appressed-pubescent between as well as upon the veins beneatli ; 

 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 Duraugo, 

 Dr. J. TV. Rose, no. 2321; also secured by the same collector between 

 Pedro Paulo and San Blascito, Topic, no. 1991. Types in herb. U. S. 

 Nat. Museum and herb. Gray. 



19. P. PELLiTUM, Klatt. Leaves thinnish, ovate-lanceolate, attenuate, 

 entire or nearly so, drying dark, the under surface covered with a very 

 fine cauescent tomentum: heads 3 to many at the ends of the branches; 

 pedicels sometimes very short, sometimes much elongated. — Leopoldiua, 

 xxiii. 143. P. discolor, Sch. Bip. ace. to Klatt, 1. c. ; Hemsl. 1. c, in 

 part ; not Schrad. — Mexico, Yavesia, Liehnann, no. 375 ; also moun- 

 tains of Orizaba, Thomas, Potteri, no. 313, Bouryeau, no. 2927, Seaton, 

 no. 125. Specimens from the Berlin Garden (1839) have elliptic obtuse 

 crenate leaves. 



20. P. DISCOLOR, 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. Getting. 1830; Linnsea, v. Lit.-Ber. 

 72 ; DC. Prodr. v. G08, excl. synon.; Hemsl. 1. c. as to plants of Oaxaca. 

 — Mountains and foothills of Oaxaca, A.ndrieux, no. 305, Prlnrjle, no. 

 4650, L. G. 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 



