A Taxonomic Study of the Genus Galium in Iowa

The genus Galiurn, a member of the Madder family (Rubiaceae), is world-wide in its distribution and includes approximately two hundred and fifty species. Ten species of Galium were enumerated by R. I. Cratty1 in his annotated list of Iowa flora. Two new species, four varieties and three forms have since been reported for the state. The present study of the genus was undertaken with two objects in view: first, to clarify our understanding of the species found in Iowa, many of these specimens having been incorrectly named, and second, to incorporate the several name changes since the last edition of Gray\u27s 2 Manual ( 1908), five of which involve Iowa species