288 PliOCEEDINGS OF THE AMERICAN ACADEMY. 



Sch. Bip. acc. to Klatt, 1. c. — Oaxaca: Galeotti, 2122, Andrieiix, 345; 

 Tehuacan, Liehmann, 267 (drawing in hb. Gr.), Schmitz, 1027 (hb. Gr.) ; 

 Coixlahuaca, Nelson, 1935, alt. 2,000 to 2,500 m., 1894 (hb. Gr.). 

 PuEBLA : Puebla, Smith, 912, alt. 2,000 m., 1895 (hb. Gr.), Pringle, 

 4749, fields, 1894 (hb. Gr., hb. J. D. S., hb. M. B. G., hb. U. S.) ; 

 Chapultepec, Schaffner, 16 (hb. Gr.) ; Hort. Mex., Berlandier, 640 

 (hb. Gr.). 



h. b. b. Leaves remotely denticulate, narrow at base; inflorescence nakerl, not 

 compact; upper stem pubescent, slender; outer bracts usually conspicuous. 



6. P. intermedia, nov. sp. Stem about 30 cm. high, slender, erect, 

 angled, purplish, pubescent, dichotomously branching, primary branches 

 in the two specimens all simple, terminated by a loose corymbiform 

 glomerule resembling that of F. campestris : leaves minutely serrate, 1.2 

 to 5 cm. long, .2 to .4 cm. wide, usually opposite, sometimes whorled 

 in axils: heads few-flowered, bracts minute to 3 mm. long: 9 achene ^- 

 larger than ^ achene. — Durango : Plains near Yermo, Pringle, 7359, 

 Oct. 1896 (hb. U. S., hb. Gr.). 



This species differs from F. linearis in having only three bracts, in 

 possessing a 9 achene much larger tlian the achene of $ flower, and 

 in form of leaves. It differs from F. campestris in its very slender stem, 

 in shape of leaves, and in size of flowers ; and from F. angnstifolia iu its 

 slender stem, comparatively loose inflorescence, and size of floral organs. 



b. b. b. b. Leaves remotely denticulate, narrowing to a petiole-like base ; stem 

 pubescent; outer bracts minute or absent. 



■ 7. F. ROBUSTA, Rose. About 1.2 m. high, pubescent or glabrate 

 below: leaves lanceolate or linear above, 4.5 to 13 cm. long, acute to 

 acuminate, tapering into a slender petiole, 3-nerved, entire or slightly 

 serrate : inflorescence open, corymbose ; heads small, with 3 involucral 

 bracts: flowers 3; ray 1, orbicular, about .2 cm. long; disk flowers 2: 

 achenes .15 cm. long. — Rose, Cont. Nat. Herb. i. 337 (1895). — Mexico : 

 Colima, Palmer, 1299, Feb. 27-28, 1891 (hb. Gr., hb. J. D. S., hb. 

 M. B. G., hb. U. S.) ; Armeria, Marcus E. Jones, 276, June 28, 1892 

 (hb. Gr., hb. U. S.) ; Chihuahua, Batopilas, E. A. Goldman, 240, 

 Oct. 1898 (hb. Gr., hb. U. S.). 



a. a. Leaves linear, bracts 5. 

 b. Stem strict. 

 8. F. LINEARIS, Lag. Stem shrubby, erect or more commonly 

 sprawling, branching indefinite, branches of unequal length; lower inter- 

 nodes short, made conspicuous by the remnants of the leaves, striate, glab- 



