Due to their pronounced intraspecific variability and to difficulties in defining their evolutionary trends in mammalian phylogenies, peripheral blood vessels have been neglected in comparative studies. Supported by the Sonderforschungsbereich 89 (Car diology) of the Deutsche Forschungsgemeinschaft, we have reconstructed the ontoge of the blood vessels of the tree shrew, Tupaia belangeri, on the netic morphogenesis basis of a series of developmental stages. The arteries of the lower extremity are described and discussed here. Besides describing the morphogenesis of the arteries in Tupaia, it...