Reviews

The Hamameli(i)dae comprise, according to the new classification by Thorne, about one quarter of the genera to one third of the families of the Dicotyledonae. The symposium held at the University of Reading, U.K, 22-25 March 1988, highlighted some of the many questions concerning phylogeny and evolution in this group as a contribution to the insight in the main lines of dicotyledonous evolution. The symposium report contains a wealth of information on a wide variety of topics. The phylogenetic position of the Hamamelidae in a wider or narrower sense, or parts thereof, is subject of a number of papers. F. EHRENDORFER reviews the existing diverging interpretations and concludes that the Hamamelidae can be regarded as ancient and partly relictual survivors from a broad transitional field between ancestors of Magnoliidae and Rosidae/Dilleniidae. R.F. THORNE maintains his interpretation of the Hamamelidae as a polyphyletic assemblage, but now submerges the Hamamelidanae into the Rosanae. W.C. DICKISON gives an interpretation concluding that the main rosid-hamamelid radiations probably descended from common ancestral stock characterised by largely unspecialised, insect-pollinated, bisexual flowers with petals.