Abstract:
The primary vascular system of the shoot of Tessana absulthioides was studied by the use of serial cross sections. It is a system of the open type, with eight sympodia, 2/5 helical phyllotaxy and trilacunar three-trace nodes. All the bundles are interpreted as leaf traces diverging towards the left along a smistrorse genetic spiral. Leaf insertion is of the separated type and there are two sets (2 ± 3) of contact parastichies in the apex. The phylogenetic implications of these characters are discussed.
