FOOTNOTES
[12] Flourens: Cours de Physiologie Comparée, 1856, p. 9.
[13] Burdach: Physiologie, ii. 245.
[14] Darwin: Origin of Species, p. 128.
[15] Isidore Geoffroy St. Hilaire: Hist. Nat. Générale des Règnes Organiques, 1860, iii. 207 sq. Broca: Mémoire sur l’Hybridité, in Brown-Sequard’s Journal de la Physiologie, 1859.
[16] See their interesting essays in Müller’s Archiv. 1856.