[124] "Animals and Plants under Domestication," vol. ii. p. 104.

[125] North British Review, New Series, vol. vii., March 1867, p. 317.

[126] "Origin of Species," 5th edition, 1869, p. 212.

[127] See also the Popular Science Review for July 1868.

[128] A bird with a keeled breast-bone, such as almost all existing birds possess.

[129] "Anatomy of Vertebrates," vol. iii. p. 792.

[130] Ibid. p. 793.

[131] As a tadpole is the larval form of a frog.

[132] As Professor Huxley, with his characteristic candour, fully admitted in his lecture on the Dinosauria before referred to.

[133] "Transactions of the Geological Society of Glasgow," vol. iii.