Numerical Analysis of the Morphological Variation in the Genus Aletris L. In North America

Abstract

This study was first proposed in 1975 and begun in 1977. Specimens on loan began arriving in early 1978, and categorization of the loan into physiographic provinces and species present within each province was the first step. Sampling and subsequent measuring required approximately one-half year, with computer analysis occupying another few months. It was not until all of the results of the analysis accumulated that I began to feel comfortable with the species as circumscribed. In a genus such as Aletris where the species seem to flow into one another, one begins to question the reliability of ranking taxa. Identification of an individual plant is sometimes possible with one or two characters, but with Aletris, as with many other genera, using as many characters as possible is the best rule. Because the species are so closely aligned, proper identification may continue to be a problem, since every plant cannot be subjected to the elaborate techniques of analysis employed in this study. I hope that the distribution maps will help narrow the choice of species present in any area, and I hope that the phenograms and PCA threedimensional models will aid by showing affinities within the genus.