CHEMICAL AND MORPHOLOGICAL ANALYSIS OF INTROGRESSIVE HYBRIDIZATION BETWEEN IRIS RENAX AND I. CHRYSOPHYLIA

Iris tenax and I. chrysophylla were collected along a linear transect extending through narrow areas of sympatry from two sites in the Willamette River drainage of western Oregon. Statistical analysis of correlations between morphological characteristics was used to construct a hybrid index for each species. Morphological evaluation and 2-dimensional paper chromatography of the major flavonoid constituents were prepared on a plant by plant basis along the transects. The combined morphological and chemical data indicated that hybridization was occurring and that, in contrast to previous reports, introgression was taking place in each of the parental species. © 1969, The New York Botanical Garden. All rights reserved.