The Variation of Animals and Plants under Domestication — Volume 1. Darwin Charles

done nothing by methodical selection; and probably very little by unintentional selection; though in each litter he generally saves the prettiest, and values most a good breed of mouse- or rat-catchers. Those cats which have a strong tendency to prowl after game, generally get destroyed by traps. As cats are so much petted, a breed bearing the same relation to other cats, that lapdogs bear to larger dogs, would have been much valued; and if selection could have been applied, we should certainly have had many breeds in each long-civilised country, for there is plenty of variability to work upon.

      We see in this country considerable diversity in size, some in the proportions of the body, and extreme variability in colouring. I have only lately attended to this subject, but have already heard of some singular cases of variation; one of a cat born in the West Indies toothless, and remaining so all its life. Mr. Tegetmeier has shown me the skull of a female cat with its canines so much developed that they protruded uncovered beyond the lips; the tooth with the fang being .95, and the part projecting from the gum .6 of an inch in length. I have heard of several families of six-toed cats, in one of which the peculiarity had been transmitted for at least three generations. The tail varies greatly in length; I have seen a cat which always carried its tail flat on its back when pleased. The ears vary in shape, and certain strains, in England, inherit a pencil-like tuft of hairs, above a quarter of an inch in length, on the tips of their ears; and this same peculiarity, according to Mr. Blyth, characterises some cats in India. The great variability in the length of the tail and the lynx-like tufts of hairs on the ears are apparently analogous to differences in certain wild species of the genus. A much more important difference, according to Daubenton (1/99. Quoted by Isid. Geoffroy 'Hist. Nat. Gen.' tome 3 page 427.), is that the intestines of domestic cats are wider, and a third longer, than in wild cats of the same size; and this apparently has been by their less strictly carnivorous diet.

      CHAPTER 1.II

       HORSES AND ASSES.

       HORSE. DIFFERENCES IN THE BREEDS. INDIVIDUAL VARIABILITY OF. DIRECT EFFECTS OF THE CONDITIONS OF LIFE. CAN WITHSTAND MUCH COLD. BREEDS MUCH MODIFIED BY SELECTION. COLOURS OF THE HORSE. DAPPLING. DARK STRIPES ON THE SPINE, LEGS, SHOULDERS, AND FOREHEAD. DUN-COLOURED HORSES MOST FREQUENTLY STRIPED. STRIPES PROBABLY DUE TO REVERSION TO THE PRIMITIVE STATE OF THE HORSE.

       ASSES. BREEDS OF. COLOUR OF. LEG- AND SHOULDER-STRIPES. SHOULDER-STRIPES SOMETIMES ABSENT, SOMETIMES FORKED.

      The history of the Horse is lost in antiquity. Remains of this animal in a domesticated condition have been found in the Swiss lake-dwellings, belonging to the Neolithic period. (2/1. Rutimeyer 'Fauna der Pfahlbauten' 1861 s. 122.) At the present time the number of breeds is great, as may be seen by consulting any treatise on the Horse. (2/2. See 'Youatt on the Horse': J. Lawrence on the Horse 1829; W.C.L. Martin 'History of the Horse' 1845: Col. H. Smith in 'Nat. Library, Horses' 1841 volume 12: Prof. Veith 'Die naturgesch. Haussaugethiere' 1856.) Looking only to the native ponies of Great Britain, those of the Shetland Isles, Wales, the New Forest, and Devonshire are distinguishable; and so it is, amongst other instances, with each separate island in the great Malay archipelago. (2/3. Crawfurd 'Descript. Dict. of Indian Islands' 1856 page 153. "There are many different breeds, every island having at least one peculiar to it." Thus in Sumatra there are at least two breeds; in Achin and Batubara one; in Java several breeds; one in Bali, Lomboc, Sumbawa (one of the best breeds), Tambora, Bima, Gunung-api, Celebes, Sumba, and Philippines. Other breeds are specified by Zollinger in the 'Journal of the Indian Archipelago' volume 5 page 343 etc.) Some of the breeds present great differences in size, shape of ears, length of mane, proportions of the body, form of the withers and hind quarters, and especially in the head. Compare the race- horse, dray-horse, and a Shetland pony in size, configuration, and disposition; and see how much greater the difference is than between the seven or eight other living species of the genus Equus.

      Of individual variations not known to characterise particular breeds, and not great or injurious enough to be called monstrosities, I have not collected many cases. Mr. G. Brown, of the Cirencester Agricultural College, who has particularly attended to the dentition of our domestic animals, writes to me that he has "several times noticed eight permanent incisors instead of six in the jaw." Male horses only should have canines, but they are occasionally found in the mare, though a small size. (2/4. 'The Horse' etc. by John Lawrence 1829 page 14.) The number of ribs on each side is properly eighteen, but Youatt (2/5. 'The Veterinary' London volume 5 page 543.) asserts that not unfrequently there are nineteen, the additional one being always the posterior rib. It is a remarkable fact that the ancient Indian horse is said in the Rig-Veda to have only seventeen ribs; and M. Pietrement (2/6. 'Memoire sur les chevaux a trente-quatre cotes' 1871.), who has called attention to this subject, gives various reasons for placing full trust in this statement, more especially as during former times the Hindoos carefully counted the bones of animals. I have seen several notices of variations in the bones of the leg; thus Mr. Price (2/7. 'Proc. Veterinary Assoc.' in 'The Veterinary' volume 13 page 42.) speaks of an additional bone in the hock, and of certain abnormal appearances between the tibia and astragalus, as quite common in Irish horses, and not due to disease. Horses have often been observed, according to M. Gaudry (2/8. 'Bulletin de la Soc. Geolog.' tome 22 1866 page 22.), to possess a trapezium and a rudiment of a fifth metacarpal bone, so that "one sees appearing by monstrosity, in the foot of the horse, structures which normally exist in the foot of the Hipparion," — an allied and extinct animal. In various countries horn-like projections have been observed on the frontal bones of the horse: in one case described by Mr. Percival they arose about two inches above the orbital processes, and were "very like those in a calf from five to six months old," being from half to three- quarters of an inch in length. (2/9. Mr. Percival of the Enniskillen Dragoons in 'The Veterinary' volume 1 page 224: see Azara, 'Des Quadrupedes du Paraguay' tome 2 page 313. The French translator of Azara refers to other cases mentioned by Huzard as having occurred in Spain.) Azara has described two cases in South America in which the projections were between three and four inches in length: other instances have occurred in Spain.

      That there has been much inherited variation in the horse cannot be doubted, when we reflect on the number of the breeds existing throughout the world or even within the same country, and when we know that they have largely increased in number since the earliest known records. (2/10. Godron, 'De l'Espece' tome 1 page 378.) Even in so fleeting a character as colour, Hofacker (2/11. 'Ueber die Eigenschaften' etc. 1828 s. 10.) found that, out of 216 cases in which horses of the same colour were paired, only eleven pairs produced foals of a quite different colour. As Professor Low (2/12. 'Domesticated Animals of the British Islands' pages 527, 532. In all the veterinary treatises and papers which I have read, the writers insist in the strongest terms on the inheritance by the horse of all good and bad tendencies and qualities. Perhaps the principle of inheritance is not really stronger in the horse than in any other animal; but, from its value, the tendency has been more carefully observed.) has remarked, the English race-horse offers the best possible evidence of inheritance. The pedigree of a race-horse is of more value in judging of its probable success than its appearance: "King Herod" gained in prizes 201,505 pounds sterling, and begot 497 winners; "Eclipse" begot 334 winners.

      Whether the whole amount of difference between the various breeds has arisen under domestication is doubtful. From the fertility of the most distinct breeds (2/13. Andrew Knight crossed breeds so different in size as a dray-horse and Norwegian pony: see A. Walker on 'Intermarriage' 1838 page 205.) when crossed, naturalists have generally looked at all the breeds as having descended from a single species. Few will agree with Colonel H. Smith, who believes that they have descended from no less than five primitive and differently coloured stocks. (2/14. 'Nat. Library, Horses' volume 12 page 208.) But as several species and varieties of the horse existed (2/15. Gervais 'Hist. Nat. Mamm.' tome 2 page 143. Owen 'British Fossil Mammals' page 383.) during the later tertiary periods, and as Rutimeyer found differences in the size and form of the skull in the earliest known domesticated horses (2/16. 'Kenntniss der fossilen Pferde' 1863 s. 131.), we ought not to feel sure that all our breeds are descended from a single species. The savages of North and South America easily reclaim the feral horses, so that there is no improbability in savages in various quarters of the world having domesticated more than one native species or natural race. M. Sanson (2/17. 'Comptes rendus' 1866