136 



FIELD COLUMBIAN MUSEUM BOTANY, VOL. III. 



series, the outer little shorter, ovate, acuminate, pubescent, appressed, 

 somewhat spreading at maturity ; inner obtuse, mucronate, pubescent 

 at the summit. Ray corollas yellow, tube slender pubescent, ligule 

 broadly oblong, 3 lobed, 5 mm. long, pubescent beneath, ascending or 

 spreading; disk corollas with 5 truncate, ciliolate lobes. Receptacle 

 convex ; scales oblong, pubescent at the abruptly acute tip, equal- 

 ing the disk flowers, persistent on the receptacle. Achene brown, 

 .65-. 7x2 mm., cylindrical-obconoid; in section obtusely 3 or 4 angled, 

 the facets subconcave; densely pale sericeous-pilose; pappus bristles 

 about 20, stramineous, silky plumose. 



Hab. Campo about Izamal, Jan. 23, 1895, Millspaugh Armour 

 Exped. 218; Yucatan, loc. ignot., Linden; Cozumel, 1885, Gaumer 

 (Oliver); common near Merida, Valdez 89; Feb. n, 1903, Ccec. 

 et Ed. Seler 3821; "herb 20 inches, very common in waste places 

 near Izamal, Jan. to Dec. Gaumer 341, Chichankanab 1566, 1745, San 

 Anselmo 1744. 



Abundant throughout, called YERBA SAN JUAN DEL MONTE, and 

 used in domestic medicine as a refrigerant. 



FLAVERIA Juss. Gen. PI., 186. 



Heads few flowered; heterogamous, i flower pistillate fertile, 

 short ligulate, the rest perfect, fertile, tubular; or homogamous all 

 tubular, or heads i flowered, ligulate or tubular, aggregated in the 

 same glomerule. Involucre ovoid or oblong, of 2-5 carinate-concave 

 bracts. Receptacle minute, naked. Achene subcompressed, 8-12 

 ribbed ; pappus none. Glabrous herbs, mostly annuals. 



Achene 10 ribbed 

 Achene 12 ribbed 



linearis. 

 trinervata. 



Flaveria linearis Lag* Gen. et Sp. Nov., 33. 



A branching herb, with striate stem and branches, and opposite, 



sessile, more or less connate, slightly fleshy, linear or linear-lanceo- 

 late, acuminate, entire leaves. In- 

 florescence a dense rounded or 

 flat-topped, compound, terminal, 

 cyme; branchlets and peduncles 

 angled, the entire inflorescence a 

 lurid pale greenish yellow. Heads 

 short-pediceled, 6 mm. high, 2.3-2.5 

 mm. broad, 5 or 6 flowered, one 

 ligulate. Involucre ovoid, of 5 ap- 

 pressed, lanceolate, acute bracts, 

 connate at the base. Ray corolla 

 yellow, tube slender, ligule suborbic- 

 ular, 2 mm. long, entire, spreading 

 or recurved, disk corollas, 5 lobed. 

 Receptacle convex. Achene black, 

 *t, .45 x 2 mm., oblanceolate-oblong, 



rounded at the summit; in section 



oval in outline, 10 angled; angles acute, facets concave ; prominently 



10 ribbed, glabrous. 



