Nodal vasculature in some bignoniaceae

Nodal vasculature in 17 genera and 20 species belonging to family Bignoniaceae was investigated. The leaves are simple in Crescentia and pinnately compound in remaining taxa. These are opposite, rarely alternate and exstipulate. The node is uniformly unilacunar one, three or many traced. The arc shape strand, ring of discrete vascular bundle or circular leaf trace gives off lateral branches at different level in nodal region, as observed in some plants are cortical bundles. The nodal evolution in family Bignoniaceae might have been evolved by reduction process. The vascular supply to each axillary bud is derived directly from the stele. The results have been discussed with respect to evolutionary conception of node.