With cats the matter is entirely different, it being the male at present that is the difficulty, if a real difficulty it may be called.
Mr. Herbert Young, a most excellent cat fancier and authority on the subject, is of opinion that if a tortoiseshell male cat could be found, it would not prove fertile with a tortoiseshell female. But of this I am very doubtful, because, if the red and the yellow tabby is so, which is decidedly a weaker colour, I do not see how it can possess more vitality than a cat marked with the three colours; in fact the latter ought, in reality, to be more prolific, having black as one of the colours, which is a strong colour, blue being only the weak substitute, or with white combined. A whole black is one of the strongest colours and most powerful of cats.
Reverting once again to the pigeon fancier by way of analogy, take, as an instance, what is termed the silver-coloured pigeon, or the yellow. These two, and duns, are, by loss of certain pigments, differently coloured and constituted (like the tortoiseshell among cats) from other varieties of pigeons of harder colours, such as blues, and blacks, or even reds. For a long time silver turbit cock pigeons were so scarce that, until I bred some myself, I had never seen such a thing; yet hens were common enough, and got from silver and blues. In the nestling before the feathers come, the young of these colours are without down, and are thus thought to be, and doubtless are, a weakly breed; yet there is no absolute diminution of strength, beyond that of colour, when silver is matched to silver; but dun with dun, these last go lower in the scale, losing the black tint, and not unfre-quently the colour is yellow; or, matched with black, breed true blacks. I am, therefore, of opinion that a tortoiseshell male and female would, and should, produce the best of tortoiseshells, both male and female.
It not unfrequently happens that from a tortoiseshell mother, in the litter of kittens there are male blacks and clear whites, and I have known of one case when a good blue and one where the mixed colours were blue, light red, and light yellow were produced, while the sisters in the litter were of the usual pure tortoiseshell markings. In such cases, generally, the latter only are kept, unless it is the blue, the others being too often destroyed. My own plan would be to breed from such black or white males, and if not successful in the first attempt, to breed again in the same way with the young obtained with such cross; and I have but little doubt that, by so doing, the result so long sought after would be achieved. At least, I deem it far more likely to be so than the present plan of using the red tabby as the male, which are easily produced, though very few are of high excellence in richness of ground tints.
If tortoiseshell-and-white are desired, then a black-and-white male may be selected, being bred in the same way as those recommended for the pure tortoiseshell, or one without white if the female has white; but on no account should an ordinary tabby be tolerated, but a red tabby female of deep colour, or having white, may be held in request, though I would prefer patches of colour not in any way barred. The gray tabby will throw barred, spotted, or banded kittens, mixed with tortoiseshell, which is the very worst form of mottling, and is very difficult to eradicate. A gray "ticking" will most likely appear between the dark colour, as it does between the black bars of the tabby.
The best black, undoubtedly, are those bred from tortoise-shell mothers or females. The black is generally more dense, and less liable to show any signs of spots, bands, or bars, when the animal is in the sun or a bright light; when this is so, it is fatal to a black as regards its chance of a prize, or even notice, and it comes under the denomination of a black tabby.
If a black and a white cat are mated, let the black be the male, blacks having more stamina, the issue will probably be either white or black; and also when you wish the black to be perpetuated, the black male must be younger. In 1884, a black female cat was exhibited with five white kittens. I have just seen a beautiful black Persian whose mother was a clear white; this, and the foregoing example, prove either colour represents the same for the purpose of breeding to colour.
For breeding black with white, take care that the white is the gray-white, and not the yellow-white; the first generally has orange or yellow eyes, and this is one of the required qualities in the black cat. If a yellow-white with blue eyes, this type of eye would be detrimental, and most likely the eyes of the offspring would have a green stain, or possibly be of odd colours.
It should be borne in mind, that black kittens are seldom or ever so rich in colour when newly born, as they afterwards become; therefore, if without spots or bars, and of a deep self brown-black, they will in all possibility be fine in colour when they gain their adult coat. This the experienced fancier well knows, though the tyro often destroys that which will ultimately prove of value, simply from ignorance. An instance of the brown-black kitten is before me as I write, in a beautiful Persian, which is now changing from the dull kitten self brown-black on to a brilliant glossy, jetty beauty.
Blue in cats is one of the most extraordinary colours of any, for the reason that it is the mixture of black which is no colour, and white which is no colour, and this is the more curious because black mated with white generally produces either one colour or the other, or breaks black and white, or white and black. The blue being, as it were, a weakened black, or a withdrawal by white of some, if not all, of the brown or red, varying in tint according to the colour of the black from which it was bred, dark-gray, or from weakness in the stamina of the litter. In the human species an alliance of the Negro, or African race, and the European, produces the mulatto, and some other shades of coloured skin, though the hair generally retains the black hue; but seldom or ever are the colours broken up as in animal life, the only instance that has come to my knowledge, and I believe on record, being that of the spotted Negro boy, exhibited at fairs in England by Richardson, the famous showman; but in this case both the parents were black, and natives of South Africa. The boy arrived in England in September, 1809, and died February, 1813. His skin and hair were everywhere parti-coloured, transparent brown and white; on the crown of his head several triangles, one within the other, were formed by alternations of the colour of the hair.