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3.

Perhaps the greatest contribution to botany made by Dr. Bessey was his phylogenetic system of taxonomy, and his last work, "The Phylogenetic Taxonomy of Flowering Plants", was one of a series of papers read by invitation at the 25th Anniversary Celebration the Missouri Botanical Garden, October 15, 1914.

Dr. Bessey died in Lincoln, Nebraska on February 25, 1915.

The Besseyan system is quite a departure from the systems we've seen up to this report. The closest parallel is to that of Engler, but the most primitive group is the Ranales, rather than the Apetalous forms, which according to Bessey, are but reduction series of the polypetaly, for example Salicaceae, which he places as an apetalous, declinicus Tamariscinae, in the Caryophyllales.

There is no group of Amentiferae, Monochlamydeae, Polypetalae, or Sympetalae, and there has been a great reduction in the number of orders, 32 in all, whereas Engler has 55. Bessey's reputation as a splitter may be somewhat over-looked, since this was the trend in his day. He lists exactly 300 families, (280 according to Kew Index), and the greatest "splitting" was done in the Compositae, or Asterales, in which he made 15 families from the tribes.

The basis of Bessey's phylogenetic system is a group of 28 dicta, or postulates. The first seven of these dicta are general, the next seven refer to general structure of the flowering plants, and the last 14 deal with the flowers of flowering plants.

Before examination of the system, it is necessary to review these "dicta" on which the system is based.

A. General Dicta

1. Evolution is not always upward, but often it involves degradation and degeneration.

2. In general, homogeneous structures (with many and similar parts) are lower, and heterogeneous structures (with fewer and dissimilar parts) are higher.