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Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1852)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1854)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1856)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1859)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1860)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1861)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1863)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1864)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1866)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1868)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1867)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1869)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1875)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1877)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1883)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1885)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1893)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1899)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1902)

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Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1913)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1841)