Bernard volume 11 page 539; Dr. Samesreuther on 'Cattle' in volume 12 page 181; Percivall in volume 13 page 47. With respect to blindness in horses see also a whole row of authorities in Dr. P. Lucas's great work, tome 1 page 399. Mr. Baker in 'The Veterinary' volume 13 page 721, gives a strong case of hereditary imperfect vision and of jibbing.) So it is in regard to cattle, with consumption, good and bad teeth, fine skin, etc. etc. But enough, and more than enough, has been said on disease. Andrew Knight, from his own experience, asserts that disease is hereditary with plants; and this assertion is endorsed by Lindley. (12/22. Knight on 'The Culture of the Apple and Pear' page 34. Lindley's 'Horticulture' page 180.)
Seeing how hereditary evil qualities are, it is fortunate that good health, vigour, and longevity are equally inherited. It was formerly a well-known practice, when annuities were purchased to be received during the life-time of a nominee, to search out a person belonging to a family of which many members had lived to extreme old age. As to the inheritance of vigour and endurance, the English race-horse offers an excellent instance. Eclipse begot 334, and King Herod 497 winners. A "cock-tail" is a horse not purely bred, but with only one-eighth, or one-sixteenth impure blood in his veins, yet very few instances have ever occurred of such horses having won a great race. They are sometimes as fleet for short distances as thoroughbreds, but as Mr. Robson, the great trainer, asserts, they are deficient in wind, and cannot keep up the pace. Mr. Lawrence also remarks, "perhaps no instance has ever occurred of a three-part-bred horse saving his 'DISTANCE' in running two miles with thoroughbred racers." It has been stated by Cecil, that when unknown horses, whose parents were not celebrated, have unexpectedly won great races, as in the case of Priam, they can always be proved to be descended, on both sides, through many generations, from first-rate ancestors. On the Continent, Baron Cameronn challenges, in a German veterinary periodical, the opponents of the English race-horse to name one good horse on the Continent, which has not some English race-blood in his veins. (12/23. These statements are taken from the following works in order:--Youatt on 'The Horse' page 48; Mr. Darvill in 'The Veterinary' volume 8 page 50. With respect to Robson see 'The Veterinary' volume 3 page 580; Mr. Lawrence on 'The Horse' 1829 page 9; 'The Stud Farm' by Cecil 1851; Baron Cameronn quoted in 'The Veterinary' volume 10 page 500.)
With respect to the transmission of the many slight, but infinitely diversified characters, by which the domestic races of animals and plants are distinguished, nothing need be said; for the very existence of persistent races proclaims the power of inheritance.
A few special cases, however, deserve some consideration. It might have been anticipated, that deviations from the law of symmetry would not have been inherited. But Anderson (12/24. 'Recreations in Agriculture and Nat. Hist.' volume 1 page 68.) states that a rabbit produced in a litter a young animal having only one ear; and from this animal a breed was formed which steadily produced one-eared rabbits. He also mentions a bitch with a single leg deficient, and she produced several puppies with the same deficiency. From Hofacker's account (12/25. 'Ueber die Eigenschaften' etc. 1828 s. 107.) it appears that a one-horned stag was seen in 1781 in a forest in Germany, in 1788 two, and afterwards, from year to year, many were observed with only one horn on the right side of the head. A cow lost a horn by suppuration (12/26. Bronn 'Geschichte der Natur' b. 2 s. 132.), and she produced three calves which had on the same side of the head, instead of a horn, a small bony lump attached merely to the skin; but we here encroach on the subject of inherited mutilations. A man who is left-handed, and a shell in which the spire turns in the wrong directions, are departures from the normal asymmetrical condition, and they are well-known to be inherited.