p 



482 Nelson : New Plants from Wyoming 



Petradoria pumila petiolaris 



Tufted like the species, 10-20 cm. high : the branches of the 

 caudex crowded, slender and more numerous, the crowns clothed 



with dead leaf bases : basal leaves numerous, narrowly linear, on 



slender (nearly filiform), petioles which arc %-j4 as long as the 

 blade ; stem leaves also linear and petioled : inflorescence similar 

 to that of the species, but less flat-topped and fewer flowered, 

 scarcely surpasshig the relatively long leaves. 



This plant w^as secured in 1897, July 17, no. 3581, in the 

 southern portion of Sweetwater Count)-. It occurred in some 

 abundance on stony hillsides In situations similar to that frequented 

 by the species. The species Petradoria piiinila (Nutt.) Greene was 

 obtained in the same rdngc during that season'. The narrow leaves 

 and their much greater relative length gives the variety a very dif- 

 ferent aspect, but I think the difference can hardly be considered 

 specific. 



- L 



Tetradymia multicaulis 



■¥ 



Wholly unarmed ; the shrubby base tufted, niuch branched^ 

 spreading-assurgent, hardly emergent from the soil : the herba* 



rpoim nnnnnl ?sf(Mii.^ nnme'rous soiiu'uhat fascicled, simnle. CtTct. 





8-15 cm. long, permanently canesccnt with a dense, appressed 



tomentum : leaves numerous but not fascicled, narrowly oblong 

 with tapering ends, acute at apex, nearly sessile, like the stems 

 permanently cancscent, 15-25 mm. long, midrib usually evident, 

 the pair of lateral nerves obscure : flowers In very compact, ter- 



minal clusters of 10-20 heads with bract-like leaves intermingled ; 



I ~^^ 



heads 12-14 mm. high, four-bracted and four-flowered: pappus- 

 copious : akenes villous. 



In color of stems and foliage and in floral characters it closely 

 resembles T, caucsccns DC. and T. imruih Nutt. but In Its caespi- 

 tose habit it is strikingly different. The numerous erect herba- 

 ceous stems arc about all that appears above the surface of the 

 soil. It should be noted, too, that these stems arc unbranched, in 

 striking contrast with the before mentioned members of this group. 

 The leaves are broader and the venation more conspicuous. 



Collected on the Laramie Plains, not far from Laramie, June 

 24, 1897, by Mr. Ellas Nelson. Type specimen In the herb. Univ. 

 of Wyoming, no. 3442' 



written 



and the plant lias been carefully dbserved in the field and again collected as no. 5062. 

 The characters as given are fully confumed by these later observations and collections- 



