Part 2, 1915] CARDUACEAE : TAGETEAE 161 



shaped throat; achenes 6-7 nun. long, hirsute, angled; squamellae 10-15, divided into 



9-12 bristles each. 



TYPS LOCALITY: Almoloyas, Oaxaca. 

 Distribution: Oaxaca. 



2. Gymnolaena serratifolia (DC.) Rydberg. 



Dyssodia serratifolia DC. Prodr. 5: 641. 1836. 



Hymenatherum serratifolium Ili-msl. Biol. Centr. Am. Bot. 3: 221. 1881. 



Dyssodia sessilifolia A. Gray, Proc. Am. Acad. 19: 37. 1883. 



A glabrous shrub; branches terete; leaves opposite, broadly lanceolate or elliptic, slv.rt- 



petioled, 3-7 cm. long, acute at each end, coarsely serrate, dark-green above, pale beneath ; 



glands many, scattered; heads corymbose-cymose; peduncles 2-5 cm. long, with several small 



conspicuously glandular bracts; involucre cylindro-campanulate, 12 mm. high, 4-6 mm. broad, 



subtended by 1 or 2 subulate accessory bracts; bracts 4-6, with triangular tips and 3 irregular 



rows of large elliptic glands; ray-flowers 8-10; ligules yellow, 5-7 mm. long; disk-corollas 8 mm. 



long, puberulent, greenish-yellow with dark nerves; tube 3 mm. long, cylindric; throat 



trumpet-shaped; lobes elongate-lanceolate; achenes 4 mm. long, appressed-hirsute, somewhat 



angled; squamellae about 10, 5-8 mm. long, each divided into 8-10 bristles. 



Type locality: Atitla, Oaxaca. 

 Distribution: Oaxaca. 



3. Gymnolaena integrifolia (A. Gray) Rydberg. 



Dyssodia integrifolia A. Gray, Proc. Am. Acad. 19: 37. 1883. 



A shrub, branches slender, glabrous, or slightly puberulent in lines; leaves oppo- 

 site, linear-lanceolate, 3-5 cm. long, subsessile or short-petioled, finely serrate with ap- 

 pressed teeth, minutely puberulent or glabrous; heads solitary or few; peduncles 5-10 cm. 

 long, with several subulate bracts; involucre cylindro-campanulate, about 15 mm. high, 6 mm. 

 broad, naked or subtended by a single linear accessory bract; bracts about 8, with lanceolate 

 or deltoid tips and usually 2 irregular rows of oblong glands; ray-flowers about 8; ligules 

 orange, oblong, about 7 mm. long; disk-corollas about 10 mm. long, yellow, with dark veins; 

 tube slightly longer than the trumpet-shaped throat; achenes 6 mm. long, hirsute with ascend- 

 ing hairs; pappus tawny, 1 cm. long; squamellae 10 or more, each divided into 9-12 bristles. 



Type locality: District of Chiapas, Chiapas. 

 Distribution: Puebla to Chiapas. 



4. Gymnolaena Seleri (Rob. & Greenm.) Rydberg. 



Dyssodia Seleri Rob. & Greenm. Proc. Am. Acad. 35: 314. 1900. 



A stoutish herb; branches terete, striate, puberulent, at length glabrate,; leaves simple, 

 opposite or subopposite, oblong, shortly acuminate, rounded or more often cordate at the 

 sessile base, sharply and rather finely serrate, 6-13 cm. long, 2.5-4 cm. wide, dotted with 

 numerous round glands; peduncles terminal, more or less clavate-thickened towards the sum- 

 mit; involucre 3 cm. broad, puberulent, glandless; accessory bracts distinct, unequal, lance- 

 olate, acute, herbaceous at least near the apex; principal bracts united two thirds their length, 

 their tips acuminate; ray-flowers 12-20; ligules (in dry state) brown, more than 1 cm. long; 

 disk-corollas nearly 1.5 cm. long; achenes sericeous-villous; pappus 1 cm. long, of about 20 

 squamellae, each dissected into several bristles. 



Type locality: Near Xochicato, Cuernavaca, Morelos. 

 Distribution: Morelos. 



5. BOEBERASTRUM (A. Gray) Rydberg, gen. now 



Dyssodia § Boeberastrum A. Gray, Proc. Am. Acad. 19: 39. 1883. 

 Hymenatherum § Heterochromea A. Gray, Syn. Fl. N. Am. V-: 446. 1884. 



Diffuse annuals. Leaves mostly alternate, fleshy. Heads radiate, short-peduncled or 



subsessile. Involucre hemispheric or broadly campanulate, without a calyculum; bracts S- 



14, in two more or less definite equal series, united at the base or to the middle, the free 



portion scarious-margined, the margins of each alternate bract slightly overlapping the inner 



