Tarweed Tribe 421 



chaffy throughout, the chaff distinct and persistent. 

 Achenes triangular, the inner angles terminated by a 

 short apiculation, nearly smooth or faintly rugose-tuber- 

 culate. Pappus none. 



1. C. pungens (H. & A.) Greene. Stout with rather rigid 

 ascending or spreading branches, 4-8 din. high, hirsute or hispid, 

 scarcely viscid, nearly or quite scentless; lower leaves 2-pinnati- 

 fid, the upper 1-pinnatifid, the lobes pungent-tipped; chaff of 

 receptacle rigid-pungent ; disk-achenes destitute of pappus ; ray- 

 achenes nearly black, about 2 mm. long, the ventral angle cari- 

 nate, the plane sides ancl rounded back faintly tuberculate- 

 rugose. 



Common in the plains in heavy, rather moist soil. July-November. 



2. C. Parryi Greene. Widely branching, 3-6 dm. high, sparsely 

 hirsute, minutely resinous-glandular, aromatic; lowest leaves 

 pinnatifid,the cauline linear, entire, sharply pungent, spreading, 

 the uppermost pilose-ciliate toward the base ; heads scattered ; ray- 

 achenes dull black, 1.5 mm. long, somewhat compressed, smooth 

 on the sides, with a few coarse tuberculations on the back ; disk- 

 achenes with 3 or more paleae exceeding the corollas; chaff of 

 the receptacle not pungent. 



Brackish flats toward the coast. June-August. 



38. DEINANDBA Greene. 



Erect, rigid and brittle, balsamic-viscid annuals, with 

 mostly small few-flowered panicled heads, and entire or 

 serrate leaves. Involucral bracts few, half enclosing 

 their achenes, their tips short, rigid and erect. Rays 

 usually 5, broad, 3-toothed, diurnal. Receptacle chaffy 

 only next the rays. Ray-achenes gibbous, tuberculate- 

 rugose, the terminal areola raised upon a distinct 

 curved beak from the angle of the ventral face of the 

 achene ; disk-achenes mostly sterile, with or without a 

 paleaceous crown. 



1. D. fasciculata (DC.) Greene. Hirsute or hispid below, 

 glabrous and viscid-glandular above, 2-5 dm. high ; heads small, 



