Part 1, 1914] CARDUACEAE : HELENIEAE 59 



Ray-fiowers wanting. 



Involucre 4—7 mm. high and broad; bracts 6-9, rarely more; leaves linear. 



Pappus-squamellae about 1 mm. long, obtuse; involucre 4—6 mm. long. 1. O. callosum. 

 Pappus-squamellae, at least those of the center, 2 mm. long, lanceolate, 



acute; involucre 6-7 mm. long. 2. O. roseum. 



Involucre 7-10 mm. high, 8-12 mm. broad; bracts 10-15; leaves of a lanceo- 

 late type. 

 Pappus-squamellae shorter than the corolla-tube, the outer ones obtuse. 

 Inner sciuamellae 3 mm. long, acutish; plant branched; bracts 



oblanccolate. ,3. O. lexanum. 



Inner squamellae 1.5-2 mm. long, obtuse; plant stout, simple; 



bracts linear. 4. O. robuslum. 



Pappus-squamellae, at least the inner ones, equaling or longer than the 

 corolla-tube, lanceolate. 

 Achenes decidedly hairy. 



Pappus-squamellae 5 mm. long, acuminate; plant wholly her- 

 baceous. 5. O. macrolepis. 

 Pappus-squamellae 3 mm. long, acute; plant often ligneous 



below. 6. O. canescens. 



Achenes glabrous or practically so. 7. O. Lindeni. 



Ray-flowers present. 



Involucre 10-15 mm. high, 10-20 mm. broad; ray-flowers 8-12; disk- 

 flowers more numerous. 

 Leaves all lanceolate or linear-lanceolate, the uppermost not much 



reduced, 3-ribbed; involucre 12-15 mm. high, 12-20 mm. broad. 8. 0. Hookerianum. 



Lower leaves lanceolate or linear-lanceolate, rarely 3-ribbed, the upper 



reduced and linear; involucre about 1 cm. high and broad. 9. O. sphacelatum. 



Involucre about 8 mm. wide; ray -flowers and disk -flowers each 3-6; leaves 



linear. 10. O. Reverchoni. 



1. Othake callosum (Nutt.) Bush, Trans. Acad. St. Louis 14: 174. 



1904. 



Stevia callosa Nutt. Jour. Acad. Phila. 2: 121. 1821. 

 Florestina callosa DC. Prodr. 5: 655. 1836. 

 Othake tenuifolium Raf. New Fl. 4: 74. 1838. 

 Palafoxia callosa T. &. G. Fl. N. Am. 2: 369. 1842. 

 Polypleris callosa A. Gray, Proc. Am. Acad. J 9: 30. 1883. 



A slender annual; stem much-branched, 2-6 dm. high, strigose, glandular-hirsute in the 



inflorescence; branches more or less flexuose, ascending; leaves short-petioled or subsessile, 



thick, linear, 2-5 cm. long, 1-3 mm. broad, strigose-hispidulous on both sides, 1-nerved; 



involucre turbinate, 4-6 mm. high and as broad; bracts about 8, strigose-hispidulous, rarely 



glandular, linear-oblanceolate, with short colored tips; ray-flowers wanting; disk-flowers 5-12; 



corollas flesh-colored; tube 2 mm. long; lobes linear, 3-4 mm. long; achenes 3-4 mm. long, 



angular, hirsutulous; squamellae obovate or spatulate, about 1 mm. long or less; costa scarcely 



reaching the apex. 



Type locality: Banks of the Arkansas [Arkansas or Oklahoma]. 



Distribution: Missouri and Arkansas to New Mexico. 



Illustrations: W. Barton, Fl. N. Am. pi. 46; Britt. & Brown, 111. Fl. /. 3966; ed. 2. f. 4535. 



2. Othake roseum Bush, Trans. Acad. St. Louis 14: 175. 1904. 



Polypleris rosea Small, Fl. SE. U. S. ed. 2. 1372. 1913. 



An annual; stem erect, comparatively simple, with strongly ascending branches, strigose- 

 hirsute, glandular above, 4-7 dm. high; leaves short-petioled, narrowly linear- lanceolate or 

 linear, 1-nerved, 2-5 cm. long, 2-5 mm. wide, strigose-hirsute ; involucre tiu-binate, 6-7 mm. 

 high and as broad; bracts 7-9, oblanceolate, strigose-hispidulous and glandular, with deep- 

 purple tips; peduncles slender; ray-flowers wanting; disk-flowers 10-15; corollas bright rose- 

 colored; tube about 3 mm. long; lobes linear, 3 mm. long; achenes 3-4 mm. long, 1 mm. thick, 

 hirsute; squamellae lanceolate, acute, about 2 mm. long, those of the marginal achenes 

 shorter and obtuse. 



Type locality: Sheldon, 18 miles east of Houston, Texas. 

 Distribution: Texas and Oklahoma. 



3. Othake texanum (DC.) Bush, Trans. Acad. St. Louis 14: 176 



1904. 



Palafoxia iexana DC. Prodr. 5: 125. 1836. 



Polypleris lexa^ta A. Gray, Proc. Am. Acad. 19: 30. 1883. 



