DISCOVERY OF A LEWIS AND CLARK GRASS COLLECTION, POA SECUNDA (POACEAE) SENSU LATO, AT THE HERBARIUM OF THE ROYAL BOTANIC GARDENS, KEW

摘要

The 2005 discovery of a specimen of Aira brevifolia Pursh (=Poa secunda J. Presl) at the Royal Botanic Garden Kew (K) collected during the 1804-1806 Lewis and Clark expedition demonstrated that the designated lectotype in the Lewis and Clark Herbarium at the Academy of Natural Sciences in Philadelphia (PH-LC) is a mixture of a June 1806 collection made in Idaho and a late July 1806 collection obtained in Montana. Accordingly, a "second step" lectotypification is proposed for the PH-LC sheet restricting application of A. brevifolia to the element Pursh had at hand in London, namely plants collected by Lewis probably near the mouth of Crow Coulee, Chouteau County, Montana, on 28 Jul 1806.