do not generally revert to any uniform colour.

[138] Dr. Sclater, in 'Proc. Zoolog. Soc.,' 1862, p. 164.

[139] W. C. Martin, 'History of the Horse,' 1845, p. 207.

[140] Col. Sykes' Cat. of Mammalia, 'Proc. Zoolog. Soc.,' July 12th, 1831.
Williamson, 'Oriental Field Sports,' vol. ii., quoted by Martin, p. 206.

[141] Blyth, in 'Charlesworth's Mag. of Nat. Hist.,' vol. iv., 1840, p. 83.
I have also been assured by a breeder that this is the case.

[142] One case is given by Martin, 'The Horse,' p. 205.

[143] 'Journal As. Soc. of Bengal,' vol. xxviii. 1860, p. 231. Martin on
the Horse, p. 205.

[144] Hermann von Nathusius, 'Die Racen des Schweines,' Berlin, 1860; and
'Vorstudien fur Geschichte,' &c., 'Schweineschaedel,' Berlin, 1864.
Ruetimeyer, 'Die Fauna der Pfahlbauten,' Basel, 1861.

[145] Nathusius, 'Die Racen des Schweines,' Berlin, 1860. An excellent
appendix is given with references to published and trustworthy drawings of
the breeds of each country.

[146] For Europe, _see_ Bechstein, 'Naturgesch. Deutschlands,' 1801, b. i.,
s. 505. Several accounts have been published on the fertility of the
offspring from wild and tame swine. _See_ Burdach's 'Physiology,' and
Godron, 'De l'Espece,' tom. i. p. 370. For Africa, 'Bull. de la Soc.
d'Acclimat.,' tom. iv. p. 389. For India, _see_ Nathusius,
'Schweineschaedel,' s. 148.

[147] Sir W. Elliot, Catalogue of Mammalia, 'Madras Journal of Lit. and
Science,' vol. x. p. 219.

[148] 'Pfahlbauten,' s. 163 et passim.

[149] _See_ Ruetimeyer's Neue Beitrage, ... Torfschweine, Verh. Naturfor.
Gesell. in Basel, iv. i., 1865, s. 139.

[150] Stan. Julien, quoted by De Blainville, 'Osteographie,' p. 163.

[151] Richardson, 'Pigs, their Origin,' &c., p. 26.

[152] 'Die Racen des Schweines,' s. 47, 64.

[153] 'Proc. Zoolog. Soc.,' 1861, p. 263.

[154] Sclater, in 'Proc. Zoolog. Soc.,' Feb. 26th, 1861.

[155] 'Proc. Zoolog. Soc.,' 1862, p. 13.

[156] 'Journal of Voyages and Travels from 1821 to 1829,' vol. i. p. 300.

[157] Rev. G. Low, 'Fauna Orcadensis,' p. 10. _See_ also Dr. Hibbert's
account of the pig of the Shetland Islands.

[158] 'Die Racen des Schweines,' s. 70.

[159] These woodcuts are copied from engravings given in Mr. S. Sidney's
excellent edition of 'The Pig,' by Youatt, 1860. _See_ pp. 1, 16, 19.

[160] 'Schweineschaedel,' s. 74, 135.

[161] Nathusius, 'Die Racen des Schweines,' s. 71.

[162] 'Die Racen des Schweines,' s. 47. 'Schweineschae