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Fig. 7.5-3. Transverse section of a vessel element in muskmellon (Cucumis). This vessel element is so much larger than all surrounding cells that it has 9 contact faces in this section alone (the surrounding cells are probably shorter than the vessel element, so if we could see the entire surface, there might be more than 20 contact faces). However, when this vessel element was first formed, is was just a small parenchyma cell about the same size as surrounding cells and probably with only about five or six contact faces (if all cells are about the same size, a transverse section would show about six contact faces like a honeycomb). As it enlarged, it pushed the surrounding cells apart and formed new contacts with cells that had originally not been next to it. Despite the fact that these cell-cell contacts were made by cells pushing up against each other (rather than being formed by a cell plate during cell division), they still are able to form pit-pairs.