Access

You are not currently logged in.

Access JSTOR through your library or other institution:

login

Log in through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Journal Article

Variation in the Mexican Cycad Dioon edule (Zamiaceae)

Loran M. Whitelock
Botanical Review
Vol. 70, No. 2 (Apr. - Jun., 2004), pp. 240-249
Published by: Springer on behalf of New York Botanical Garden Press
Stable URL: http://www.jstor.org/stable/4354476
Page Count: 10
Were these topics helpful?
See somethings inaccurate? Let us know!

Select the topics that are inaccurate.

Cancel
  • Read Online (Free)
  • Subscribe ($19.50)
  • Add to My Lists
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Variation in the Mexican Cycad Dioon edule (Zamiaceae)
Preview not available

Abstract

The Mexican cycad Dioon edule with its two varieties, edule and angustifolium, range from the states of Tamaulipas and Nuevo León in the north to the state of Veracruz in the south. The variety angustifolium is restricted to the northern portions of the range, while the variety edule is from the southernmost distribution in central Veracruz. Between the two varieties of Dioon edule there are a number of disjunct colonies that exhibit variations that are undoubtedly the result of an extended period of genetic isolation. These colonies display variation in the maximum size of their stems, morphology and color of leaves and leaflets, distinctions in both male and female cones, color of the sarcotesta, and size and shape of the sclerotesta. These differences are maintained even when specimens are grown in cultivation under identical conditions. Critical investigations of these colonies may ultimately disclose the need for additional species descriptions.

Page Thumbnails

  • Thumbnail: Page 
240
    240
  • Thumbnail: Page 
241
    241
  • Thumbnail: Page 
242
    242
  • Thumbnail: Page 
243
    243
  • Thumbnail: Page 
244
    244
  • Thumbnail: Page 
245
    245
  • Thumbnail: Page 
246
    246
  • Thumbnail: Page 
247
    247
  • Thumbnail: Page 
248
    248
  • Thumbnail: Page 
249
    249
Part of Sustainability