The period of origins for legal theories concerning maritime jurisdiction of fisheries is from the earliest expression of a theory of the legal status of the sea—or a little before—to 1648, the year of the Treaty of Westphalia, when all the theories concerned with this subject and with maritime jurisdiction of fisheries reached their maturity, or at least their point of extreme development. This is the period to which Percy Thomas Fenn has sharply limited his study—a field that has hitherto been practically untouched. The footnotes provide extensive quotations from the sources, partly because they are not to be found outside a few great libraries and partly because the peculiarities of diction often make them of extreme interest and importance. The very complete bibliography will serve the needs of other investigators in this department of jurisprudence and history.