Part 2, 1915] 



CARDUACEAE : HELENIEAE 



111 



Plant low, densely canescent ; heads 1^3; squamellae not 

 more than half as long as the corolla, not subulate- 

 tipped. 

 Plant tall, greener; heads several or many; squamellae 

 about half as long as the corolla, subulate- tipped. 

 Leaves of the stem not conspicuously numerous, glabrate and 

 green; segments 1—3 mm. wide. 

 Heads large; involucre 12-15 mm. broad. 

 Heads small; involucre 10 mm. broad or less. 

 Leaves, at least the lower ones, entire or with broad lobes 3-8 

 mm. wide. 

 Otiter bracts about 12; stem low. 

 Outer bracts 15-20; stem tall, about 5 dm. high. 

 Annuals (rarely biennials) with numerous heads; inner bracts not very 

 different from the outer, neither abruptly acute nor mucronate, 

 nor evidently erose ; throat of the disk-corollas somewhat funnel- 

 form. 

 Leaves pinnatifid into linear divisions; rays conspicuous. 

 Heads large; involucre 12 mm. broad or more. 

 Squamellae awn-pointed. 

 Squamellae muticous. 

 Heads small; involucre 10 mm. broad or less. 

 Plant annual. 



Outer bracts with loose, somewhat acuminate tips; plant 



often more than 3 dm. high. 

 Outer bracts with appressed acute tips; plant seldom more 

 than 3 dm. high. 

 Plant biennial. 

 Leaves entire or merely toothed or lobed; rays minute. 



14. //. canescens. 



15. //. biennis. 



16. //. I.emmoni. 



17. H. Greenei. 



18. H. subintegra. 



19. H. helenioides. 



20. H. chrysanthemoides. 



21. //. insignis. 



22. H. excurrens. 



23. H. odorata. 



24. H. Davidsonii. 



25. H. lexana. 



1. Hymenoxys Richardsoni (Hook.) Cockerell, Bull. Torrey Club 



31: 468. 1904. 



Picradenia Richardsoni Hook. Fl. Bor. Am. 1: 317. 1833. 

 Actinella Richardsoni Nutt. Trans. Am. Phil. Soc. II. 7: 379. 1841. 

 Hymenopappus ligulaeflorus A. Nelson. First Rep. Fl. Wyo. 135. 1896. 

 Picradenia ligulaeflora A. Nelson, Bull. Torrey Club 25: 378. 1898. 

 Hymenoxys Richardsoni ligulaeflora Cockerell, Bull. Torrey Club 31: 474. 1904. 

 Hytnenoxys ligulaeflora Cockerell, Bull. Am. Mus. Nat. Hist. 22: 422. 1906. 



A cespitose perennial, with a woody eaudex; stems several, 1-2 dm. high, villous-puberulent. 

 striate, somewhat branched; heads few or solitary; leaves 4-10 cm. long, 3-cleft into narrowly 

 linear divisions, strongly punctate, sparingly puberulent or glabrate; peduncles 2-6 cm. 

 long; involucre 6 mm. high, 9-12 mm. broad; outer bracts 10-12, united about halfway up; 

 free portion of the bracts ovate or ovate-lanceolate, abruptly acute with a slightly raised 

 midrib; inner bracts as many, ovate, erose-fimbriate on the margins, acute; ligules yellow, 5- 

 8 mm. long; disk-corollas 3 mm. long, puberulent; tube almost wanting; throat cylindro- 

 campanulate; achenes 4 mm. long, densely hirsute; squamellae 2 mm. long, lanceolate, gradually 

 attenuate into an awn-point. 



Type locality: Carlton House, Saskatchewan. 

 Distribution: Saskatchewan and Alberta to Wyoming. 

 Illustration: Hook. Fl. Bor. Am. pi. 108. 



Hymenoxys macrantha (A. Nelson) Rydb. Bull. Torrey Club 

 33: 156. 1906. 



Picradenia macrantha A. Nelson. Bot. Gaz. 28: 130. 1899. 



Hymenoxys Richardsoni macrantha Cockerell, Bull. Torrey Club 31: 475. 



1904. 



A cespitose perennial, with a short woody eaudex covered with hairy leaf-bases; stems 

 sparingly puberulent, 1-2 dm. high; leaves 4-10 cm. long, pinnately divided into 3-5 narrowly 

 linear segments, sparingly hairy, soon glabrate, not conspicuously punctate, the uppermost 

 entire; heads several; peduncles 2-5 cm. long; involucre 7-8 mm. high, 12-15 mm. broad; 

 outer bracts 10-12, united only about one third their length; free portion lanceolate, acute; 

 inner bracts elliptic, acute, scarious and erose on the margin; ray-flowers 6-10; ligules chrome- 

 yellow, 10-18 mm. long, 5-6 mm. wide; disk-corollas 4-5 mm. long, glandular-puberulent ; tube 

 about 1 mm. long; achene 5 mm. long, densely hirsute; squamellae lanceolate, 2.5-3 mm. long, 

 tapering into an awn-point. 



Type locality: Fort Steele. Wyoming. 

 Distribution: Wyoming. Utah, and Colorado. 



