[412]

Ibid. pp. 77, 78.

[413]

Balfour, op. cit. p. 16.

[414]

See Chapter XI.

[415]

Pettigrew, Animal Locomotion, Internat. Sci. Series, London, 1874, p. 64; Gadow, Science for All (Cassell), v. p. 302.

[416]

Bridge, Journ. Linn. Soc. (Zool.), xxv. 1896, p. 530.