The Artemisia ludoviciana polyploid complex is a highly polymorphic
assembledge of eight taxa in the Pacific Northwest, with a
chromosome base number of x=9. A cytogenetic analysis of this
complex was carried out to determine the sources of its variation,
the types of polyploidy present, and the genetic processes active...
A cytogeographic study, the relationship between chromosome
number and geographical and ecological distribution, was made of the
tetraploid and hexaploid chromosome forms of Achillea millefolium L.
in western Oregon. Principal objectives of the investigation were
three. First was a determination of the exact distributions of the two
levels, as previous...