1919] Hall: Chrijsothamnus nmiseosus and Its Varieties 169 



to 10 mm. long). C. iorinosus Greene, Pitt., vol. 5, p. 63, 1902, is 

 aparently a form intermediate between this and speciosus. It is 

 described as having tortuous flowering branches, nearly filiform more 

 or less spreading leaves which are also tortuous, and rather pungenth' 

 acute bracts. The types came from Plumas County- and Mount Shasta, 

 California. 



7. Chrysothamnus nauseosus var. speciosus (Xutt.) comb. nov. 



Chrysothamnus speciosus Nutt., Trans. Am. Pliilos. Soc, ser. 2, vol. 7, p. 323, 

 1841. 



Shrub commonly 6 to 20 dm. high, broad and rounded, leafy to 

 summit : twigs greenish white, the tomentum comparatively thin and 

 smooth : leaves 2 to 6 cm. long, typically about 1 mm. wide but varying 

 to 3 mm., usually erect or ascending, becoming dense towards the 

 inflorescences and there scarcely reduced in size, gray, tomentose or 

 the tomentum partly deciduous and the foliage then greenish : inflor- 

 escence a round-topped or somewhat elongated cyme, commonly loose : 

 involucre 7 to 10 mm. high ; bracts 3 or 4 in each row, acute, concave, 

 tomentulose on the back, not ciliate : corolla 8 to 10 mm. long ; tube 

 sparsely puberulent or glabrous ; lobes 0.8 to 2 mm. long. 



The above description is drawn to include a number of forms. 

 In this broad sense speciosus has a range from Idaho and Utah to 

 California and Washington. It is a variety belonging to sandy slopes 

 and benches with little or no alkali. The type came from "the Rocky 

 ^Mountain plains, near Lewis River" and was described as having 

 narrow, linear, acute, more or less tomentose leaves and heads in 

 dense, conglomerate, terminal clusters. A form which answers to 

 this but with a slightly elongated and loose inflorescence is common 

 from northern Utah to eastern Oregon and northern California where, 

 through the nearly glabrous character of the involucre it passes into 

 occidentalis. Further south in eastern California and western Nevada 

 the involucre becomes more compact and nicely rounded but in this 

 form the comparatively rigid leaves are 2 to 3 mm. wide and vary 

 from gray to yellowish green. This type was apparently included by 

 Dr. Greene in his californicus. In the absence of better characters 

 and with our scant knowledge of the real speciosus it seems unwise 

 to segregate these forms more definitely at present, although they are 

 more striking than many of the Rocky ^Mountain varieties accepted 

 in this paper. C. pulcJurritnus, A. Nels., Bot. Gaz., vol. 28, p. 370, 

 1899, is a form of the high plains of the Rocky Mountain states, 

 especially in moist soil. All of the characters used to differentiate 

 it from speciosus are variable and no two of tliera vary in unison, but 



