The supplemental observation by EM is made for the phellem of Melaleuca leucadendra L. The EM survey clearly provides the site of "casparian strip" on the anticlinal wall of short cell. The "casparian strip" in the young cell is more conspicuous than that in the older cell. The wrinkled wall exhibits only on the anticlinal wall of young short cell. Basing on the absence of plasmodesmata, cytoplasmic contents and the presence of "casparian strip", the short cell is suggested as more specialized than the long cell. The cell expansion occurs after the appearance of suberized wall.