relationships within the Magnoliidae show a trend of reduction of floral parts and the change 
from spiral to whorled phyllotaxis of perianth, stamens and carpels. Spiral phyllotaxis is present 
in Hortonia, but such condition is not known among the Lauraceae. Furthermore, in the other 
taxa of the Monimiaceae closely related to that genus both spiral and whorled phyllotaxis is 
present. This suggest that the ancestor to the Lauraceae might be somewhere in between 
Hortonia and its closest relatives in the Atherospermatoideae or the Monimioidae. In any case, 
an original condition of fixed whorled phyllotaxis for the ingroup is assumed. 0, flowers trimerous; 
1, flowers dimerous or tetramerous. 
9. Flower sex. Both perfect and unisexual flowers occur in the Lauraceae, but the perfect 
condition is most common. Perfect flowers have usually been considered to be the plesiomorphic 
condition for sex distribution within the Magnoliidae, and the Lauraceae are not the exception. 
Besides, Hortonia is with perfect flowers too. 0, flowers perfect; 1, flowers unisexual. 
10. Position of floral parts with respect to pistil. The hypanthium is taken here as 
receptacular in origin. Thus, position of floral units is actually the one that is observed. The 
hypanthium, either shallow or deep, is widely present within the Monimiaceae (Hortonia has it) 
as well as in the Lauraceae, and then the perigynous condition of the perianth and the stamens is 
considered plesiomorphic. The application of the outgroup algorithm suggested by Maddison et 
al. (1984) to the phylogenetic trees presented in Qiu et al. (1993) supports this conclusion. The 
changes to hypogynous or epigynous conditions could have occured several times, and it is not 
sure that shifts from hypogynous to epigynous position, or viceversa, can be overruled to have 
happened. So, changes between states are unordered. 0, perianth and stamens hypogynous; 1, perianth 
and stamens perigynous; 2, perianth and stamens epigynous. 
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