You are not currently logged in.
Access JSTOR through your library or other institution:
If You Use a Screen ReaderThis 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.
Variation Patterns and Recognition of Varieties of Tilia americana s.l.
James W. Hardin
Vol. 15, No. 1 (Jan. - Mar., 1990), pp. 33-48
Published by: American Society of Plant Taxonomists
Stable URL: http://www.jstor.org/stable/2419014
Page Count: 16
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.
Preview not available
The taxonomy of the North American basswoods is problematical. Recently, the choice has been to recognize either four poorly defined species (one in Mexico and three in the United States), based mainly on vestiture, or alternatively, two species (one in Mexico and only one in the U.S.) based mainly on geography. Given the inconstancy of most vegetative and reproductive characters, the ecophenic, ecotypic, and seasonal variation in vestiture, and also the probability of introgression, the morphology of trichomes, described by SEM, emerges as the character set that provides the best evidence for four taxa. These four, each with definable geographical ranges but with broad zones of intergradation, are treated as varieties of T. americana: vars. americana, heterophylla, caroliniana, and mexicana (comb. nov.).
Systematic Botany © 1990 American Society of Plant Taxonomists