“…However, the distribution within the subfamily is very orderly. 13,4, 8,31,II,8 Ko 10 -12.5 Kaeor 4,8,10,8,13,15,9,13,16 Kao 7,10,14 Kae 8,9,9 Ke9 Nb ! This orderly division of the grass family into two distinct groups seems to suggest (Brown and Smith, 1972) that the Kranz syndrome arose relatively early in the evolution of the family and may prove useful for establishing broad phylogenetic relationships. For example, can the tribe Paniceae or the genus Panicum contain both Kranz and non-Kranz species?…”