ROBINSON AND GREENMAN, — TRIXIS. T 
bracts and 5 to 10 equal erect linear-oblong scales: corollas yellow, 
strongly bilabiate, the upper erect lip 2-cleft, the lower spreading, 
3-toothed or subentire: anthers sagittate and bicaudate at the base: 
achenes cylindrical or slightly flask-shaped, slender, finely papillose, the 
summit more or less expanded into a circular disk bearing copious simple 
roughish white or tawny pappus-bristles. — Hist. Jamaic. 312 (1756) ; 
Lag. Amen. Nat. i. 35; La Llav. & Lex. Nov. Veg. Desc. fase. 1, 27 ; 
Spreng. Syst. iii. 501; D. Don, Trans. Linn. Soc. xvi. 186, 297; DC. 
Prodr. vii. pt. 1, 67; Benth, & Hook. f. Gen. ii. 501; Hemsl. Biol. 
Cent.-Am. Bot. ii. 257; Hoffm. in Engl. & Prantl, Nat. Pflanzenf. 
iv. Abt. 5, 350; Hook. f. & Jacks. Ind. Kew. ii. 1130, which see for 
generic synonymy. Perdicium, L. Pl. Afr. Rar. 22 (1762), in part. 
About 35 species, ranging from Arizona to Brazil and Chili. 
§ 1. Inflorescence an elongated conical thyrsus : herbaceous. 
1. T. michuacana, La Liav. & Lex. Viscid-resinous and with a 
heavy odor; root fibrous, yellowish; stem simple, tomentose, 1 dm. 
high, erect: leaves sessile, punctate, villous below, the floral gradually 
reduced : heads borne in a large conic-oblong thyrsus; outer bracts of 
the involucre 5, ample, ovate, the inner involucre prismatic, of 8 erect 
scales. — Nov. Veg. Desc. fase. 1, 28 (1824); DC. Prodr. vii. pt. 1, 68; 
Hemsl. Biol. Cent.-Am. Bot. ii. 258. —- Micwoacan: near Valliso- 
letum, flowering in January, Lexarza. If the above (compiled) descrip- 
tion is correct, this is a marked species, not yet rediscovered. 
§ 2. Inflorescence corymbose-paniculate: shrubs or undershrubs. 
Leaves sessile bya clasping shortly decurrent base. 
2. T. decurrens, DC. Stems several, sparingly branched toward 
the summit: leaves crowded, ovate-lanceolate, acutely acuminate, entire: 
heads terminal, subsolitary ; outer involucre of 5 ovate-lanceolate bracts, 
the inner of 8 scales: corollas yellow. — Prodr. vii. pt. 1, 68 (1838), 
whence the foregoing description; Hemsl. Biol. Cent.-Am. Bot. ii. 
258; A. DC. Calques des Dess. t. 515. Perdicium decurrens, Sessé & 
_ Mocifio, ace. to DC. 1. c. (1838), & Pl. Nov. Hisp. ed. 2, 130.— 
Moreos: Ayacapixtla, flowering in November, Sessé § Mocitiio. 
* * Stem provided at least at some stages of its development with broad and 
conspicuous herbaceous win 
+ Outer bracts of the involucre lanceolate, much shorter than the inner; the 
latter glandular. 
3. T. mexicana, La Liav. & Lex. A meter or more high: leaves 
lanceolate, 5 to 13 cm. long, 1 to 4 cm. broad, acuminate, acute, entire 
