A monograph of the genus Rosa in North America. I. R. acicularis

  title={A monograph of the genus Rosa in North America. I. R. acicularis},
  author={Walter Hepworth Lewis},
  • W. Lewis
  • Published 15 January 1959
  • Biology
  • Brittonia
Summary(1)Rosa acicularis Lindl., the only species ofRosa indigenous to both North America and Eurasia, has the most extended distribution of any species in the genus.(2)The populations ofR. acicularis Lindl. in North America and Eurasia differ by nine morphological characters: pedicel glandulation, auricle width, number of serrations per half leaflet, kind of leaflet serration, serration glandulation, leaflet glandulation, petiole bristles, number of leaflets per leaf, and width of the sepal… Expand

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