Simpson: Coat-Patterns in Mammals 339 



Bibliography 



W. E. Cistb: "Hiriity of Cji^. Caara^csrs," Carns^is Pab, N:). 23, February, 1905; "Color 

 Variedes of R^daats," S:i3ri23, Aa?a3fc30,1907; "ANiw C^br Variety of tha Guinea Pig," 

 Sdense, August 30, 190/; — aniSimpsDn: " A Faiiily ofSpattsi Nigroas," Amsrican Natural- 

 ist, January, 1913. 



W. J. Spillman: "Inheritance of Coat Color in Swine," Science, October 5, 1906; "Color In- 

 heritance in Mammals," Science, February 27, 1907; " Inheritance of the Belt in Hampshire 

 Swine," Science, April 5, 1907. 



Q. I. and J. P. Simpson: "Reversion," Science, March 15, 1907; "Genetics in Swine Hybrids," 

 Science, June 19, 1908; "Analytical Hybridizing," American Breeders', Vol. VII, 1911; 

 "Genetic Laws Applied," A. B. A. Vol. V. 1909. 



O. Riddle: "Fundamental Bars in Feathers," Biological Bulletin, February, 1907. 



G. C. and C. B. Davenport: "Heredity of Skin Pigmentation in Man," American Naturalist, 

 November, 1910. 



H. E. Jordan: "Microscopic Study of Melanin," American Naturalist, November, 1910. 



H. H. Laughlin: "Inheritance of Color in Short Horns," American Naturalist, December, 1911, 

 January, 1912. 



J. H. Kastle and G. D. Buckner: "Asymmetric Color Resemblance in the Guinea Pig," American 

 Naturalist, September, 1912. 



A. L. Hagedorn: "Tri-Color Coat in Dogs and Guinea Pigs," American Naturalist, November, 

 1912. 



T. H. Morgan: "Factors and Unit Characters," American Naturalist, January, 1913. 



H. D. Goodale and Morgan: "Tri-Color in Guinea Pigs," American Naturalist, June, 1913. 



C. C. Little and J. C. Phillips: "A Cross Involving Four Pair of Factors in Mice," American 

 Naturalist, December, 1913. 



E. N. Wentworth: "Color in Short Horns," American Breeders' Magazine, December, 1913. 



W. W. Smith: "Color Inheritance in Swine," American Breeders' Magazine, June, 1913. 



Hemophilia in Horses 



That blood-vessel breaking in race horses is an inherited character is argued by 

 J. B. Robertson in the Bloodstock Breeders' Review (II, 4, 265), who traces the 

 beginning of the trouble to Herod, an English Thoroughbred foaled in 1758. Only 

 one runner out of 400, each year, breaks a blood-vessel, but Mr. Robertson shows 

 that the animals which do so are all found to be related, and apparently to carry 

 this pathological factor as a recessive in either sex. Ordinarily, he remarks, "a 

 true recessive character, such as chestnut coat-color, only becomes patent in the 

 individual when a determining factor for it has been inherited from both parents," 

 but it appears to him that "in certain characters which depend on structural or 

 physiological peculiarities and which are marked departures from normality, one 

 intense dose of the usually latent or abnormal character may be sufficient to over- 

 come the normal condition, which has been inherited from the sound parent." 



Inheritance in Poultry 



Several suggestions regarding inheritance in domestic fowl are made by D. F. 

 Laurie, poultry expert of the government of South Australia, in his report on Egg- 

 Laying Competitions held at Parafield in 1913-14. "I would again impress upon 

 breeders," he remarks, "that the reappearance of broodiness among White Leg- 

 horns is a taint, even as are cases of colored feathers. Both can be eliminated, 

 but only by strict and accurate methods of breeding. ... To breed from a hen 

 which at any time has shown the slightest indication of broodiness is in my opinion 

 the height of folly." The instinct to brood may be transmitted through the cocks, 

 the breeder is reminded. Mr. Laurie also considers egg-shell color to be a trans- 

 mitted character, subject to dilution or masking. There seems to be some corre- 

 lation between tinted shells and broodiness. It is considered possible that the 

 habit of laying tinted-shelled eggs appears only in alternate generations. Experi- 

 ments are now under way which are expected to yield definite conclusions on these 

 points. 



