264 American Midland Naturalist Monograph No. 2 



6. Outer bracts 4 or 5, rarely much exceeding the disk; achenes angled 4- 

 6 mm. long; corollas 5-toothed; stamens exserted; wet ground 

 throughout 111. Sept. -Oct B. connata Muhl. 



6. Outer bracts 6-8, foliaceous, exceeding the disk; achenes flat, 7-9 mm. 

 long; corollas 4-toothed; stamens included; wet ground throughout 

 111. Sept.-Oct B. comosa (Gray) Wieg. 



I.Rays present, conspicuous. 



7. Leaves simple, oblanceolate to linear-lanceolate, acuminate, serrate, con- 

 nate at the base; heads nodding in fruit; achenes cuneate, 4-angled, the 

 4 awns retrorsely barbed; wet ground, chiefly in the n. half of the 

 state. July-Oct. [B. gracilenta Greene; B. glaucescens Greene; B. lepto- 

 poda Greene; B. prionophylla Greene; B. filarnentosa Rydb.; B. elliptica 



(Wieg.) Gleason] B. cerniia L. 



7. Leaves pinnately parted or dissected; achenes flat. 



8. Outer bracts 8-10, ciliolate or glabrous, not exceeding the inner; (awns 

 sometimes only 0.5 mm. long). 

 9. Achenes obovate; moist ground along roads, or in swales and fields 



throughout 111., except the n.w. counties. Aug. -Oct 



B. aristosa (Michx.) Britt. 



9. Achenes cuneate; moist ground throughout 111. July-Oct. [5. tricho- 

 sperma (Michx.) Britt.} Plants with narrow leaf-segments have 



been named B. coronata var. tenuiloba (Gray) Sherff 



B. coronata (L.) Britt. 



8. Outer bracts 12-20, coarsely hispidulous, mostly longer than the inner; 

 swampy ground, not common; known from Cook, Kankakee, La 

 Salle, Henry, and Henderson counties. July-Sept. [5. involucrata 

 sensu Britt., non Phil.] B. polylepis Blake 



34. Megalodonta Greene — Water-marigold 



M. beckii (Torr.) Greene. Ponds and slow streams, rare. Aug. -Sept. 

 Known in 111. from Lake and Cook counties [Bidens beckii Torr.} 



Tribe 8. Helenieae 



35. Hymenopappus L'Her. 



H. scabiosaeus L'Her. Open sandy woods, rare. Mason, Cass, and Kanka- 

 kee counties. May-June. [H. carolinensis (Lam.) Porter}. 



36. Actinea Juss. 



(Picradeiiia Hook.) 



A. herbacea (Greene) B. L. Robins. Dry gravelly banks, .stony fields, and 

 limestone hills, near Joliet, Will Co., Hill, May 9, and 27, 1902, June 8, 1907; 

 H. C. Corvles, May 13, 1906; Manito, Mason Co., /. Voss. Also in Ottawa 

 Co., Ohio, and s. Ontario, Canada. [Tetraneuris herbacea Greene; Actinella 

 icaposa var. glabra Gray}. 



