o Dr. Lucas, 'L'Hered. Nat.,' tom. ii. p. 310.

[137] 'Hered. Nat.,' tom. ii. pp. 112-120.

[138] Sir H. Holland, 'Chapters on Mental Physiology,' 1852, p. 234.

[139] 'Gardener's Chronicle,' 1860, p. 270.

[140] Mr. N. H. Smith, Observations on Breeding, quoted in 'Encyclop. of
Rural Sports,' p. 278.

[141] Quoted by Bronn, 'Geschichte der Natur,' b. ii. s. 170. _See_ Sturm,
'Ueber Racen,' 1825, s. 104-107. For the niata cattle, _see_ my 'Journal of
Researches,' 1845, p. 146.

[142] Lucas, 'l'Heredite Nat.,' tom. ii. p. 112.

[143] Mr. Orton, 'Physiology of Breeding,' 1855, p. 9.

[144] Boitard and Corbie, 'Les Pigeons,' 1824, p. 224.

[145] 'Les Pigeons, pp. 168, 198.

[146] 'Das Ganze,' &c., 1837, s. 39.

[147] 'The Pigeon Book,' p. 46.

[148] 'Physiology of Breeding,' p.22; Mr. Hewitt, in 'The Poultry Book,' by
Tegetmeier, 1866, p. 224.

[149] Boitard and Corbie, 'Les Pigeons,' 1824, p. 226.

[150] 'Bastarderzeugung,' s. 256, 290, &c. Naudin ('Nouvelles Archives du
Museum,' tom. i. p. 149) gives a striking instance of prepotency in _Datura
stramonium_ when crossed with two other species.

[151] Flourens, 'Longevite Humaine,' p. 144, on crossed jackals. With
respect to the difference between the mule and the hinny, I am aware that
this has generally been attributed to the sire and dam transmitting their
characters differently; but Colin, who has given in his 'Traite Phys.
Comp.,' tom. ii. pp. 537-539, the fullest description which I have met with
of these reciprocal hybrids, is strongly of opinion that the ass
preponderates in both crosses, but in an unequal degree. This is likewise
the conclusion of Flourens, and of Bechstein in his 'Naturgeschichte
Deutschlands,' b. i. s. 294. The tail of the hinny is much more like that
of the horse than is the tail of the mule, and this is generally accounted
for by the males of both species transmitting with greater power this part
of their structure; but a compound hybrid which I saw in the Zoological
Gardens, from a mare by a hybrid ass-zebra, closely resembled its mother in
its tail.

[152] Mr. Hewitt, who has had such great experience in raising these
hybrids, says ('Poultry Book,' by Mr. Tegetmeier, 1866, pp. 165-167) that
in all, the head was destitute of wattles, comb, and ear-lappets; and all
closely resembled the pheasant in the shape of the tail and general contour
of the body. These hybrids were raised from hens of several breeds by a
cock-pheasant;