Abstract
Based on observations made in the native habitat in Uruguay, P. axillaris sensu latogrowing in southeastern and northwestern departments were considered as typical subsp.axillaris and subsp. parodii, respectively. Among 30 morphological characters, differencesin 18 of them between typical subsp. axillaris and subsp. parodii were significant. Sevendiscriminant functions discriminating these 2 subspecies from each other were calculated, and plants from 49 locations in the whole of Uruguay were predicted as subsp. axillarisor subsp. parodii by substituting the measurements into the thus obtained functions. Subspecies axillaris and parodii were southeastern and northwestern taxa, respectively, separated roughly by the river Rio Negro. There were 4 exceptional locations along the lowerstream of the Rio Negro in which intermediate forms between subsp. axillaris and parodiiwere found. Subspecies axillaris in the southwestern department possessed a corolla-tubelonger than that of the typical one. Occurrence of intergradation between subsp. axillarisand subsp. parodii was suggested even on the Uruguayan side of the Plata region.
