[9] Chamberlin. Jour. of Geol., Vol. V, p. 795.

[10] A thoroughgoing study of the Formation of Sand Dunes (by V. Cornish) is to be found in the Geog. Jour., Vol. IX, 1897, pp. 278–309.

[11] Blanford. Geology of India, 2d ed., p. 455 et seq.

[12] Cornish, loc. cit.

[13] Cornish, loc. cit., p. 294.

[14] Diller states (17th Ann. Rept., U. S. Geol. Surv., Pt. I, p. 450) that on the coast of Oregon the slope of dunes is sometimes 40°.

[15] From folio preface, U. S. Geol. Surv.

[16] Credner. Elemente der Geologie, 6th ed., p. 271.

[17] Merrill. Rocks, Rock Weathering, and Soils, p. 295.

[18] Cowles. The Ecological Relations of the Vegetation of the Sand Dunes of Lake Michigan. Botanical Gazette, Vol. XXVII, 1899. An excellent study of the relations of sand dunes and vegetation.