[27] 'Edinburgh New Phil. Journal,' July, 1863.
[28] Some great anatomists, as Cuvier and Meckel, believe that the tubercle one side of the hinder foot of the tailless Batrachians represents a sixth digit. Certainly, when the hinder foot of a toad, as soon as it first sprouts from the tadpole, is dissected, the partially ossified cartilage of this tubercle resembles under the microscope, in a remarkable manner, a digit. But the highest authority on such subjects, Gegenbaur (Untersuchung. zur vergleich. anat. der Wirbelthiere: Carpus et Tarsus, 1864, s. 63), concludes that this resemblance is not real, only superficial.
[29] For these several statements, see Dr. Struthers, in work cited, especially on intermissions in the line of descent. Prof. Huxley, 'Lectures on our Knowledge of Organic Nature,' 1863, p. 97. With respect to inheritance, see Dr. Prosper Lucas, 'L'Hérédité Nat.,' tom. i. p. 325. Isid. Geoffroy, 'Anom.,' tom. i. p. 701. Sir A. Carlisle, in 'Phil. Transact.,' 1814, p. 94. A. Walker, on 'Intermarriage,' 1838, p. 140, gives a case of five generations; as does Mr. Sedgwick, in 'Brit. and Foreign Medico-Chirurg. Review,' April, 1863, p. 462. On the inheritance of other anomalies in the extremities, see Dr. H. Dobell, in vol. xlvi. of 'Medico-Chirurg. Transactions,' 1863; also Mr. Sedgwick, in op. cit., April, 1863, p. 460. With respect to additional digits in the negro, see Prichard, 'Physical History of Mankind.' Dr. Dieffenbach ('Journ. Royal Geograph. Soc.,' 1841, p. 208) says this anomaly is not uncommon with the Polynesians of the Chatham Islands.
[30] 'The Poultry Chronicle,' 1854, p. 559.
[31] The statements in this paragraph are taken from Isidore Geoffroy St. Hilaire, 'Hist. des Anomalies,' tom. i. pp. 688-693.
[32] As quoted by Carpenter, 'Princ. of Comp. Physiology,' 1854, p. 480.
[33] Müller's 'Phys.,' Eng. translat., vol. i. 1838, p. 407. A thrush, however, was exhibited before the British Association at Hull, in 1853, which had lost its tarsus, and this member, it was asserted, had been thrice reproduced: I presume it was lost each time by disease.
[34] 'Monthly Journal of Medical Science,' Edinburgh, 1848, new series, vol. ii. p. 890.
[35] 'An Essay on Animal Reproduction,' trans. by Dr. Maty, 1769, p. 79.
[36] Bonnet, 'Œuvres d'Hist. Nat.,' tom. v., part i., 4to. edit., 1781, pp. 343, 350, 353.