class="sc">English Carrier ... 140

20. English Barb ... 145

21. English Fantail ... 147

22. African Owl ... 149

23. Short-faced English Tumbler ... 152

24. Skulls of Pigeons, viewed laterally ... 163

25. Lower Jaws of Pigeons, seen from above ... 164

26. Skull of Runt, seen from above ... 165

27. Lateral view of Jaws of Pigeons ... 165

28. Scapulæ of Pigeons ... 167

29. Furculæ of Pigeons ... 167

30. Spanish Fowl ... 226

31. Hamburgh Fowl ... 228

32. Polish Fowl ... 229

33. Occipital Foramen of the Skulls of Fowls ... 261

34. Skulls of Fowls, viewed from above, a little obliquely ... 262

35. Longitudinal sections of Skulls of Fowls, viewed laterally ... 263

36. Skull of Horned Fowl, viewed from above, a little obliquely ... 265

37. Sixth Cervical Vertebræ of Fowls, viewed laterally ... 267

38. Extremity of the Furcula of Fowls, viewed laterally ... 268

39. Skulls of Ducks, viewed laterally, reduced to two-thirds of the natural size ... 282

40. Cervical Vertebræ of Ducks, of natural size ... 283

41. Pods of the Common Pea ... 328

42. Peach and Almond Stones, of natural size, viewed edgeways ... 337

43. Plum Stones, of natural size, viewed laterally ... 345

THE

VARIATION OF ANIMALS AND PLANTS

UNDER DOMESTICATION.

INTRODUCTION.

The object of this work is not to describe all the many races of animals which have been domesticated by man, and of the plants which have been cultivated by him; even if I possessed the requisite knowledge, so gigantic an undertaking would be here superfluous. It is my intention to give under the head of each species only such facts as I have been able to collect or observe, showing the amount and nature of the changes which animals and plants have undergone whilst under man's dominion, or which bear on the general principles of variation. In one case alone, namely in that of the domestic pigeon, I will describe fully all the chief races, their history, the amount and nature of their differences, and the probable steps by which they have been formed. I have selected this case, because, as we shall hereafter see, the materials are better than in any other; and one case fully described will in fact illustrate all others. But I shall also describe domesticated rabbits, fowls, and ducks, with considerable fullness.

The subjects discussed in this volume are so connected that it is not a little difficult to decide how they can be best arranged. I have determined in the first part to give, under the heads of the various animals and plants, a large body of facts, some of which may at first appear but little related to our subject, and to devote the latter part to general discussions. Whenever I have found it necessary to give numerous details, in support of any proposition or conclusion, small type has been used. The reader

will, I think, find this plan a convenience, for, if he does not doubt the conclusion or care about the details, he can easily pass them over; yet I may be permitted to say that some of the discussions thus printed deserve attention, at least from the professed naturalist.

It may be useful to those who have read nothing about Natural Selection, if I here give a brief sketch of the whole subject and of its bearing on the origin of species.