Part 2, 1915] CARDUACEAE : TAGETEAE 175 



9. Thymophylla Treculii (A. Gray) Small, Fl. SE. U. S. 1295. 1903. 



Hymenatherum Treculii A. Cray. Proc. Am Acad. 19: 42. 

 Dyssodia Treculii B. I.. Robinson, Proc Am. Acad. 49: 508. 1913. 



A glabrous perennial, scarcely fruticose at tin- base; stem diffusely branched, 1-2 dm. 

 high; leaves opposite or alternate, 1-2 cm. long, pectinately pinnatifid into 5-13 linear, approxi- 

 mate, short segments; peduncles 3-5 cm. long; involucre hemispheric, 6 mm. high and 8 mm. 

 broad, glabrous, with 5-8 lanceolate accessory bracts; principal bracts in a single series, wholly 

 coalescent up to the triangular, short-acuminate free tips; glands mostly 1 or 2 on each bract; 

 ligules 3 mm. long, 1.5 mm. wide; disk-corollas 3 mm. long; tube shorter than the trumpet- 

 shaped throat; lobes ovate; achenes 3 mm. long, sparingly hispidulous on the angles; 

 squamellae 10, in two series, the inner 3 mm. long, with an awn between the two lobes of 

 the apex, the outer oblong, 1 mm. long. 



Type locality: Southeastern Texas. 

 Distribution: Texas and Coahuila. 



10. Thymophylla Hartwegii (A. Gray) Wooton & Standley, Contr. 

 U. S. Nat. Herb. 16: 191. 1913. 



llymenalherum Berlandieri Benth. PI. Hartw. 18. 1839. Not H. Berlandieri DC. 1836. 



Hymenatherum Hartwegii A. Gray, PI. Wright. 1: 117. 1852. 



Tageles aristata Klatt, Leopoldina 25: 109. 1889. 



Dyssodia Hartwegii B. L. Robinson, Proc. Am. Acad. 49: 507. 1913. 



A sparingly and minutely puberulent perennial, suffruticose at the base; leaves opposite, 



2-3 cm. long, pinnatifid, with 5-7 filiform spinulose-tipped divisions; peduncles filiform, 



3-5 cm. long; involucre turbinate, about 5 mm. high and nearly as broad, minutely pruinose- 



puberulent, with 1-4 small lanceolate or subulate accessory bracts; principal bracts united and 



wholly coalescent up to the triangular, short-acuminate free tips; glands 3-5; ligules 5 mm. 



long, 1.5 mm. wide; disk-corollas 3 mm. long; tube shorter than the trumpet-shaped throat; 



achenes fully 2 mm. long, hispidulous on the angles; squamellae 10, in 2 series, ihe inner 2 



mm. long, awn-tipped, the outer 0.5-0.7 mm. long, oblong. 



Type locality: Aguas Calientes. 



Distribution: Arizona and New Mexico to Aguas Calientes. 



11. Thymophylla aurantiaca (Brand.) Rydberg. 



Hymenatherum aurantiacum Brand. Zoe 5: 25S. 1908. 



Dyssodia aurantiaca B. L. Robinson, Proc. Am. Acad. 49: 507. 1913. 



A perennial, with a woody caudex; stems 1-2 dm. high; leaves alternate, 2-3 cm. long, 



pinnatifid, with 5-7 linear divisions, glabrous, fleshy, with numerous glands; peduncles 1-1.5 cm. 



long; involucre turbinate, 5 mm. high, 6-8 mm. broad, without calyculum; bracts 9-14, keeled 



below, united to near the apex, with deltoid tips and 2-6 glands; ray-flowers about 6; ligules 



yellow, 4 mm. long; disk-corollas 3 mm. long; tube shorter than the funnelform throat; achenes 



2 mm. long, angled and striate; squamellae 8-10, ovate-lanceolate, divided into 3 bristles 



(rarely with two minute additional bristles), the middle bristle much longer. 



Type locality: Cerro de Santa Lucia, Puebla. 

 Distribution: Puebla. 



12. Thymophylla Thurberi (A. Gray) Wooton & Standley, Contr. 

 U. S. Xat. Herb. 16: 191. 1913. 



Hymenatherum tenui folium var. A. Gray, PI. Wright. 2: 93. 1853. 

 Hymenatherum Thurberi A. Gray, Proc. Am. Acad. 19: 41. 1883. 

 Dyssodia cupulala A. Nelson, Bot. Gaz. 47: 435. 1909. 

 Dyssodia Thurberi B. L. Robinson, Proc. Am. Acad. 49: 508. 1913. 



A pubescent perennial, suffruticose at the base; stems 1-2 dm. high, diffusely branched, 

 finely short-pilose; leaves mostly opposite, sessile, 1.5-3 cm. long, pinnatifid into 5-7 narrowly 

 filiform spinulose-tipped divisions, short-pilose; peduncles slender, 4-S cm. long; involucre 

 turbinate-campanulate, 4-5 mm. high, 5-6 mm. broad, naked or with 1-3 minute subulate 

 accessory bracts; principal bracts in two series, united high up, the inner broader, with triangu- 

 lar tips and 3-5 glands near the apex, the outer linear, acute, with the ciliate free margins decur- 



