Butler University Botanical Studies Volume 2 Butler University Botanical Studies Article 7 Chromosome Numbers in Certain Species of Helianthus Florence Geisler Butler University Follow this and additional works at: http://digitalcommons.butler.edu/botanical The utleB r University Botanical Studies journal was published by the Botany Department of Butler University, Indianapolis, Indiana, from 1929 to 1964. The cs ientific ourj nal featured original papers primarily on plant ecology, taxonomy, and microbiology. Recommended Citation Geisler, Florence (1931) "Chromosome Numbers in Certain Species of Helianthus," Butler University Botanical Studies: Vol. 2, Article 7. Available at: http://digitalcommons.butler.edu/botanical/vol2/iss1/7 This Article is brought to you for free and open access by Digital Commons @ Butler University. It has been accepted for inclusion in Butler University Botanical Studies by an authorized administrator of Digital Commons @ Butler University. For more information, please contact
[email protected]. CHROMOSOME NUMBERS IN CERTAIN SPECIES OF HELlANTHUS By FLORENCE GEISLER INTRODUCTION some Bot. The genus Helianthus is a comparatively large one, contaInIng, ac pI. ct cording to Watson (13), 108 authentic and several doubtful species. These are arranged and classified by the taxonomist according to mani Bot. festations that are readily visible, but, if the chromosome number and the behavior during meiosis were known in each case, a better under Plant standing could be gained of the interrelation of the species and greater r grib. accuracy might be possible in deciding whether a doubtful plant were a variety, a true species or a hybrid. '/iflorn Up to now, the chromosomes have been counted in two species.