CHAPTER VIII. 



BOTANY. 



By Asa Gray. 



LIST OF PLANTS COLLECTED BY THE BLACK HILLS SURVEY. 



I. POLYPETAL^S. 



Clematis alpina Mil]., var. occedentalis, subvar. tenuiloba. 



Stems very short, hardly, if at all, climbing ; divisions of the leaves 

 lanceolate or ovate-lanceolate and acute or acuminate, pinnately 3-7-cleft 

 or parted, the longer and narrower lobes commonly almost linear ; sepals 

 acuminate ; staminodia all linear, hairy, and more or less antheriferous, not 

 half the length of the sepals, little exceeding the true stamens. All the 

 American forms, which are confined to the Rocky Mountains, from the 

 Black Hills of Dakota to New Mexico, agree in having only narrow and 

 antheriferous exterior stamens or staminodia, none of which are dilated 

 into petals, and the foliage is finer than in any of the ordinary forms of the 

 old world species, except Ledebour's Atragene macropetala and Regel's 

 A. alpina var. tenuiseda. In PI. Fendlerianse I had referred the American 

 form to A. Ochotensis ; but it is best to regard it as an independent variety 

 of that polymorphous species which takes the name of Clematis alpina. The 

 present form of it (tenuiloba) is so remarkable for the fine dissection of its 

 leaves that it would most naturally pass for a distinct new species. It 

 appears to be the analogue of Regel's A. alpina var. tenuiseda. 



Clematis ligusticifolia Nutt, 

 Anemone patens var. nuttalliana Gray. 



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