The morphology of tracheary elements of 5 plants common in maquis formations in Greece was examined. 2 of them are trees (Ceratonia siliqua and Olea europaea ssp. oleaster), possess only vessels, and their vessel members exhibit simple perforation plates. The other 3 evergreen sclorophyllous shrubs examined (Quercus coccifera, Pistacia lentiscus and Myrtus communis) possess small and more primitive tracheary elements. Q. coccifera possesses tracheids, narrow and long vessel members, and wide and short ones, all with simple perforation plates. P. lentiscus exhibits small vessel members of various diameters whose perforation plates are invariably simple. M. communis tracheary elements are represented by vessel members and very long vasculartracheids; vessel members of M. communis exhibit simple, scalariform, and transitional forms between simple and scalariform perforations. Although the examined plants are not phylogenetically related, they possess tracheary elements whioh exhibit some primitive characters, with the exception of C. siliqua which possesses the most specialized vessel members. The presence of simple perforation plates (a specialized type of perforation with high efficiency in water conductivity) in the evergreen sclerophyllous plants supports the assumption that they are well adapted to the drought conditions of the mediterranean type of climate, an assumption which might indicate a kind of convergence.