Licence: In copyright
Credit: Reports to the Evolution Committee of the Royal Society. 1-5. Source: Wellcome Collection.
Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.
100/526 (page 96)
![white, showing a mixture of the parental characters both in colour- and shape. 5. Carnage.—The attitude of the crosses is much more like I.G. than Leghorn. Though not so reachy as a fine Indian Game, they never have the general appearance of Leghorn. This appearance is doubtless due to the fact that the hard, close feathering of the LG. is always in some degree dominant. 6. Ecjcjs.—The shells are usually of intermediate tint. Eggs brown enough or white enough to pass for pure I.G. or pure L. are decidedly rare. 7. Broodiness.—Many of the cross-breds became broody and made fair mothers. Some were very imcertain, but perhaps not more so than many hens of sitting breeds. Some did not go broody at all. In regard to colour of eggs, fertility, and broodiness, for want of opportunities no extensive observations were made.] INIoreover, for any adequate study of most of the other points enumerated, it is necessary that the chickens should be reared to maturity. To do this Avith large numbers is quite beyond our resources. Fortiuiately, how- ever, the comb-structure can be determined with certainty in very young chicks at about the 14th day of incubation. By the use of this fact the range of available statistics has been greatly increased. For by opening the eggs on the 15th day, the same incubator can be filled more frequently, and the serious expense of raising many hundreds of chickens is so far dispensed with.* As stated above, the single comb is always single and can be recognised as such from an early stage. Besides variations in size and straightness, single combs sometimes have as a defect one or two lateral processes or sprigs at the hinder end. This is a fault to which the best strains are occasionally liable. The pea comb in cross-breds varies greatly as described, ranging through many inter- mediate forms towards the single comb. In counting chickens as pea-combed, it will be understood therefore that most of them would undoubtedly have had intermediate^ pea combs on reaching maturity, but none would have had single combs. An attempt was made at first to distinguish pea combs from intermediate pea combs, but this was afterwards abandoned as un- reliable. Latterly when the eye became trained, it was fairly easy to * When, in these results, the numbers of cases recorded for comb, foot-character, or colour differ, it must be understood that for some reason one or more specimens were only available for certain determinations. For example, a certain number of chicks which died too early (generally about the 10th day) for the comb- or colour- character to be made out with certainty, might show the foot-characters perfectly t in such a case the one character is reckoned and the others are left undetei-mmed. Consequently there is sometimes, as in Experiments 37 and 38, an apparent dis- crepancy between the numbers given for comb or foot character taken separately, and those given for both in combination.](https://iiif.wellcomecollection.org/image/b22652188_0100.jp2/full/800%2C/0/default.jpg)
