2/01/2007 I need to produce a general and map of the major features of leaf architecture mapped on to the latest APG 2004 cladogram. One interesting issue in this regard is the concept of the multi-stranded mid-rib and its occurrence. It would be good to break down the multi-stranded into an concept of fundamental veins which are those that radiate from the tip of the petiole and occur as separate strands there. These veins can often remain separate as in Psilotophyllum or become aggregated into a multi-stranded primary vein