SIEVE-ELEMENT CHARACTERS OF TICODENDRON

Among the families of Hamamelidae, Ticodendron incognitum Gomez-Laurito & Gomez P. contains S-type sieve-element plastids, the specifics of which (diameter and starch grains) would place it within or close to Betulaceae/Corylaceae. The absence of persistent, nondispersive P-protein bodies in the sieve elements of Ticodendron excludes the families of the Urticales and the Fagaceae, all regularly containing presistent P-protein bodies, from the list of its closet relatives.