ANIMAL PRODUCTION. 175 



The false rib, A, Borgeaud {Terre Vaud., 3 (1911), No. 50, pp. Ji55, J^oG; 

 abs. in Internat. Inst. Agr. [Rome], Bui. Bur. Agr. Intel, and Plant Diseases, 

 3 (1912), No. 2, pp. Ji58, 459). — A critical discussion of tlie views of Bi&ler 

 and Pag&s, who consider that an abnormal number of floating ribs is a sign of 

 a good dairy cow, but a fault to be avoided in draft and meat animals. 



Notes on heredity, W. J. Spillman (Amer. Nat., ^5 (1911), No. 536, pp. 

 501-512; J,6 (1912), Nos. 5^2, pp. 110-120; 5//3, pp. 163-165; 5-'f5, pp. 309- 

 312). — The author reviews the recent worli of Doncaster, Morgan, Loeb, Gortuer, 

 and others who have reported investigations on inheritance in plants and 

 animals, as previously note<l. 



The general trend of the problems of development and inheritance, A. 

 Greil (Zool. Jahrb., AM. Allg. Zool., 31 (1912), No. 3, pp. 303-518).— A discus- 

 sion vof the problems connected with embryology or the development of the 

 individual, and inheritance or the development of the race. 



Darwinism and human life, J. A. Thomson (London, 1911, pp. XII +251, 

 pi. 1). — This book contains a series of lectures, given before the South African 

 Association for the Advancement of Science in 1909, and which treat prin- 

 cipally of the factors concerned in variation and heredity. A bibliography of 

 books on heredity, variation, and evolution is appended. 



The value of pedigree, J. Wilson (Live Stock Jour. Ahnanac {London], 

 1912, pp. lOff-lOG). — The value of knowing the pedigrees of breeding animals is 

 pointed out, although a long pedigree is no guaranty that invariably the off- 

 spring will possess the qualities of near or remote ancestors. Though not so 

 stated, the applications of Mendel's law in breeding horses and cattle are illus- 

 trated by a number of examples, and formulated into general principles* as 

 follows : 



"We now know that most characters that make stock what they are run in 

 pairs, a masking and a masked character." "It is easy to eliminate a masking 

 character, but difficult to breed it pure, and it is difficult to eliminate a masked 

 character, but easy to breed it pure." 



A new method of proving Delboeuf's law, H. Hugttet and A. Lhoste (Rev. 

 Y6t. [Toulouse], 36 (1911). No. 10, pp. 605-61); ahs. in Internat. Inst. Agr. 

 [Rome], Bui. Bur. Agr. Intel, and Plant Diseases, 3 (1912), No. 1, pp. 202-204, 

 pl_ J). — A new method of proving mathematically that however large may be 

 the number of individuals similar to itself, and however small the number of 

 individuals different from itself, from which an isolated organism may arise, 

 the time will arrive when the descendants that have varied will outnumber 

 those that have not varied, providing the different generations breed in the 

 same manner. 



On the general theory of the influence of selection on correlation and 

 variation, K. Pearson (Biometrilca, S (1912), No. 3-4, pp. .J37-////.3).— This is 

 a mathematical proof that certain formulas used by the author do not depend 

 for their accuracy on the frequency being Gaussian in character. 



" They are really peculiar to the general idea of the manifold linear variate u 

 which gives the maximum correlation coefficient of an (n+l)th variate with n 

 ether variates. They do not involve any idea of continuity or any hypothesis 

 as to the nature of the selected means, standard deviations, and correlations 

 beyond the fundamental assumption that the selected population really exists 

 inside the unselected population." 



The application of the correlation coefficient to Mendelian distributions, 

 E. C. Snow (Biometrika, 8 (1912), No. 3-4, pp. ^20-^2-^).— Several criticisms 

 are made of methods previously noted (E. S. R., 24, p. 374), and a demonstration 

 of one is given to show that the method of finding correlation must be deter- 



