Drift Mounds near Olyinpia^ Wash. — Rogem. 393 
Gen.et sp. nov. Protodus jexi. Sp. nov. Acanthodes semistriat- 
icus, Diplodns prohlematiciis. 
68. 'Woodward, A. S.— The Evolution of Fins. 
Nat. Sci., i, pp. 28-35, 111. 
■Wortman, J. L. — See Nos. 53 and 54. 
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The Auk, viii. No. 4, Oct., 365-68. 
Notice in Nat. Sci., i, p. 270. 
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PALJEONTOLOGY, 1891-92. 
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72. —Id. pp. 328-38. 
73. Burmeister, H.— Arch. Anat. Phys. A. f. Phys. 1891. 
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76. Moreno, F., andMercerat, A. — Les Pajaros Fosiles de la Repub- 
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Brit. Assn. Rept., 1891, p. 635. 
DRIFT MOUNDS NEAR OLYMPIA, WASHINGTON. 
By G. O. Rogers, Dorchester, Mass. 
Nature's architecture is always interesting, often beautiful; but 
frequentl}' the history of a structure presents man}- perplexing- 
difficulties to solve. Toward the western coast of Washington, a 
few miles south of Olympia, are found an immense number of pe- 
culiar tumuli, from three to five feet high, thirt}' feet more or less 
in diameter, regular in size, having the form of a broad-based cone, 
composed of a heterogeneous mass of sand and gravel, enclosing 
plentiful water-worn pebbles and cobbles, such as usually appear 
in modified glacial drift. These mounds cover a large area, em- 
bracing hundreds of acres, for the most part open prairie, with a 
ver}' slight westerly dip. The forests, however, have encroached 
to such an extent that large numbers of the mounds are found 
within the timber. They can be numbered by thousands, and are 
