[Footnote 4: In American Journal of Science, July, 1860, pp. 148, 149.]
[Footnote 5: In Contributions to the Nat. Hist. of U. S., Vol. i. pp. 128, 129.]
[Footnote 6: Contr. Nat. Hist. U.S., Vol. i. p. 130; and Amer.
Journal of Science, July, 1860, p. 143.]
[Footnote 7: North American Review, for April, 1860, p. 506.]
[Footnote 8: Vide mottoes to the second edition of Darwin's work.]
[Footnote 9: North American Review, l.c. p. 504.]
[Footnote 10: North American Review, l.c. p. 487, et passim.]
[Footnote 11: In American Journal of Science, July, 1860, p. 143.]
[Footnote 12: Vide article by Mr. C. Wright, in the Mathematical
Monthly for May last.]
[Footnote 13: Vide Edinburgh Review for January, 1860, article on
"Acclimatization," etc.]