FOOTNOTES:
[163] See A. Agassiz, Three Cruises of the Blake (Cambridge, Mass., 1888), vol. i. p. 127, footnote.
[164] Even the extremely fine Mississippi mud is nowhere found beyond a hundred miles from the mouths of the river in the Gulf of Mexico (A. Agassiz, Three Cruises of the Blake, vol. i. p. 128).
[165] I have given a full summary of the evidence for the permanence of oceanic and continental areas in my Island Life, chap. vi.
[166] For a full account of the peculiarities of the Madagascar fauna, see my Island Life, chap. xix.
[167] See Island Life, p. 446, and the whole of chaps. xxi. xxii. More recent soundings have shown that the Map at p. 443, as well as that of the Madagascar group at p. 387, are erroneous, the ocean around Norfolk Island and in the Straits of Mozambique being more than 1000 fathoms deep. The general argument is, however, unaffected.
[168] For some details of these migrations, see the author's Geographical Distribution of Animals, vol. i. p. 140; also Heilprin's Geographical and Geological Distribution of Animals.
[169] For a full discussion of this question, see Island Life, pp. 390-420.
[170] Géographie Botanique, p. 798.
[171] Nature, 1st April 1886.