[42] J. M. Eaton ‘Treatise on the Breeding and Managing of the Almond Tumbler,’ 1851. Compare p. v. of Preface, p. 9, and p. 32. [43] ‘Treatise on Pigeons,’ 1852, p. 41. [44] Eaton’s ‘Treatise on Pigeons,’ 1858, p. 86. [45] _See_ Neumeister’s figure of the Florence Runt, tab. 13 in ‘Das Ganze der Taubenzucht.’ [46] Mr. W. J. Moore gives a full account of the Ground Tumblers of India (‘Indian Medical Gazette,’ Jan. and Feb. 1873), and says the pricking the base of the brain, and giving hydrocyanic acid, together with strychnine, to an ordinary pigeon, brings on convulsive movements exactly like those of a Tumbler. One pigeon, the brain of which had been pricked, completely recovered, and ever afterwards occasionally made somersaults. CHAPTER VII. FOWLS. BRIEF DESCRIPTIONS OF THE CHIEF BREEDS—ARGUMENTS IN FAVOUR OF THEIR DESCENT FROM SEVERAL SPECIES—ARGUMENTS IN FAVOUR OF ALL THE BREEDS HAVING DESCENDED FROM GALLUS BANKIVA—REVERSION TO THE PARENT-STOCK IN COLOUR—ANALOGOUS VARIATIONS—ANCIENT HISTORY OF THE FOWL—EXTERNAL DIFFERENCES BETWEEN THE SEVERAL BREEDS—EGGS—CHICKENS—SECONDARY SEXUAL CHARACTERS—WING-AND TAIL-FEATHERS, VOICE, DISPOSITION, ETC—OSTEOLOGICAL DIFFERENCES IN THE SKULL, VERTEBRÆ, ETC—EFFECTS OF USE AND DISUSE ON CERTAIN PARTS—CORRELATION OF GROWTH. As some naturalists may not be familiar with the chief breeds of the fowl, it will be advisable to give a condensed description of them.[1] From what I have read and seen of specimens brought from several quarters of the world, I believe that most of the chief kinds have been imported into England, but many sub-breeds are probably still unknown here. The following discussion on the origin of the various breeds and on their characteristic differences does not pretend to completeness, but may be of some interest to the naturalist. The classification of the breeds cannot, as far as I can see, be made natural. They differ from each other in different degrees, and do not afford characters in subordination to each other, by which they can be ranked in group under group. They seem all to have diverged by independent and different roads from a single type. Each chief breed includes differently coloured sub-varieties, most of which can be truly propagated, but it would be superfluous to describe them. I have classed the various crested fowls as sub-breeds under the Polish fowl; but I have great doubts whether this is a natural arrangement, showing true affinity or blood relationship. It is scarcely possible to avoid laying stress on the commonness of a breed; and if certain foreign sub-breeds had been largely kept in this country they would perhaps have been raised to the rank of main-breeds. Several breeds are abnormal in character; that is, they differ in certain points from all wild Gallinaceous birds. At first I made a division of the breeds into