This work originated in a series of lectures on meson and baryon ex- cited states which I gave at the Stanford Linear Accelerator Center in the fall of 1962. The notes of these lectures were issued as a Stanford Uni- versity report (SLAC-13) in March, 1963. In the fall of 1963, I gave a revised set of lectures on meson and baryon spectroscopy at Indiana University. In both cases, the talks were given primarily for experi- mental physicists. In preparing the notes of these talks for pUblication, I have added some introductory material on pions, nucleons, kaons, and hyperons. My main emphasis is on the experimental facts concerning the spectros- copy of the mesons and baryons and on the use of conservation laws in their interpretation. I have either mentioned briefly or omitted entirely explanations which depend on dynamical models. Although I have given a number of facts about the electromagnetic and weak decays of some mesons and baryons, I have not discussed the theory of these decays. This is not a comprehensive review of the subject of the strongly interacting particles, and the list of references is not complete. Also, I have not always devoted time to a subject in proportion to its impor- tance, but have spent more time on topics which have particularly interested me. Nevertheless, I hope that I have provided a useful summary of the most important facts about the spectroscopy of the mesons and baryons.

This work originated in a series of lectures on meson and baryon ex- cited states which I gave at the Stanford Linear Accelerator Center in the fall of 1962. The notes of these lectures were issued as a Stanford Uni- versity report (SLAC-13) in March, 1963. In the fall of 1963, I gave a revised set of lectures on meson and baryon spectroscopy at Indiana University. In both cases, the talks were given primarily for experi- mental physicists. In preparing the notes of these talks for pUblication, I have added some introductory material on pions, nucleons, kaons, and hyperons. My main emphasis is on the experimental facts concerning the spectros- copy of the mesons and baryons and on the use of conservation laws in their interpretation. I have either mentioned briefly or omitted entirely explanations which depend on dynamical models. Although I have given a number of facts about the electromagnetic and weak decays of some mesons and baryons, I have not discussed the theory of these decays. This is not a comprehensive review of the subject of the strongly interacting particles, and the list of references is not complete. Also, I have not always devoted time to a subject in proportion to its impor- tance, but have spent more time on topics which have particularly interested me. Nevertheless, I hope that I have provided a useful summary of the most important facts about the spectroscopy of the mesons and baryons.