It is true that the number of our own species has lately been placed as high as a thousand, but even if these figures are correct, the seeds of decay from internal causes, such as inbreeding and the degeneration of restraint, are already sown, and the inevitable end of the race is not far off.

The bison is on the danger line; if it survives the fatal effects of its natural sluggishness when abundantly fed, it still runs the more insidious but equally great danger of inbreeding, like the wild ox of Europe.

That this deterioration of both body and antlers is due partly to long continued elimination of the best bulls, and partly to inbreeding, is probable.

This is probably due to killing off the big bulls, thus leaving the breeding to be done by the smaller and weaker bulls; and, also, to inbreeding.

They were thin and long-legged and many of the rams had four horns, apparently due to centuries of inbreeding and the failure to improve the original stock by the introduction of new and superior strains.

The black and tan thereupon went quite out of favour, and this fact, coupled with the reckless amount of inbreeding of red to red that has been going on since Ptero's day, accounts largely for the prevalence of light eyes, pink noses, and bad-coloured coats of the Dachshunds, as a class, to-day.

All these terriers had intense quality and style, due for the most part to inbreeding.

He was apparently too much inbred to, and though he produced or was responsible for several beautiful terriers, it is much to be doubted whether in a breed which is suffering from the ill-effects of too much inbreeding, he was not one of the greatest sinners.

There is a white blaze on the forehead, in the centre of which should be a clear lozenge-shaped chestnut spot, called the beauty spot, which by inbreeding with other varieties is fast being lost.

Broadly speaking, two methods have been adopted: The method of introducing an outcross to impart new blood, new strength, new character; and the method of inbreeding to retain an approved type.

Inbreeding is the reverse of outcrossing.

There is no surer way of maintaining uniformity of type, and an examination of the extended pedigree of almost any famous dog will show how commonly inbreeding is practised.

Inbreeding is certainly advantageous when managed with judgment and discreet selection, but it has its disadvantages also, for it is to be remembered that faults and blemishes are inherited as well as merits, and that the faults have a way of asserting themselves with annoying persistency.

Inbreeding maintains a fineness of breed, but at the cost of its vigor.

That inbreeding is harmful is fairly certain.

The Polynesians must have remarked that inbreeding accentuated the faults in a strain, making for an accumulation of them.

The inbreeding consequent upon this paucity of sponge life has produced a certain fixity of character in fresh-water sponges, and is in direct opposition to the effects of hybridization in the salt-water sponges, by which they have acquired the capacity of adapting themselves to local circumstances.