IN a recent communication1, Mia reports the presence of nuclei and cytoplasm in mature vessel elements and fibre tracheids, and states that his findings are contrary to the observations of Esau and of Eames and MacDaniels in their text-books of plant anatomy. Mia's interpretations of the statements are very loose. He quotes Esau2: “in the mature state, tracheids and vessel members… with lignified walls” are “devoid of protoplasts”, and “after the secondary wall is fully formed and lignified, the swollen parts of the primary wall break down and finally the protoplasts break down and disappear”. Esau's statements certainly cover the possible existence of a protoplast in a vessel element after the primary wall of the perforation plate breaks down. She does not state that disappearance of pore wall and protoplast coincide.