CORRECTIONS OF THE CHROMOSOME-NUMBER, DISTRIBUTION AND MISIDENTIFICATIONS OF THE FEDERALLY ENDANGERED SUNFLOWER, HELIANTHUS-SCHWEINITZII T-AND-G

Helianthus schweintizii was designated as a Federally endangered speci es in 1991. Since that time, an intensive research effort has been car ried out on the species. The taxonomic typification is clarified throu gh the examination of all the pertinent material. Examination of the h istorical background of Lewis David von Schweinitz allows a theory of the location of the original collection site. Misidentifications of th e species before it was well known produced incorrect distributions an d led to a report of chemical compounds attributed to this species, bu t which in fact occur in another sunflower. These identifications are corrected. The reported chromosome number of n = 51 (hexaploid), based on one collection that cannot be relocated, is corrected to 2n = 68 ( tetraploid), based on 33 counts from eight populations.