EXPERIMENT STATION RECOED. 665 



ANIMAL PRODUCTION. 



An important contribution to statistical theory, R. Peael {Amer. Nat., ^8 

 (1914), No. 572, pp. 505-507). — The author eonmients on Slutsky's recent con- 

 tribution extendins Pearson's test for the goodness of fit to cover the chiss of 

 curves formerly not amenable to such test, and the importance of this contri- 

 bution to biunu'trlcians. 



The distribution of a Mendelian population in successive generations with 

 continued brother X sister mating, R. Pearl (Amer. Nat., 48 (1914), ^o. 565, 

 pp. 5S-G.i). — Starting with a population composed, entirely of complete hetero- 

 zygotes as to a single character, the author follows out the distribution in suc- 

 cessive generations with continued brother X sister mating up to the tcnith 

 generation. He shows that the proportion of homozygotes approaches 100 per 

 cent in the same miinner as in the case of self-fortilization, but at a slower x'ate. 



Studies on inbreeding. — IV, On a general formvila for the constitution of 

 the nth generation of a Mendelian population in which all matings are of 

 brother X sister, K. Pkahl (Amer. Nat., 4S (1914), No. 57.1, pp. 491-494).— The 

 author endeavors to i)iit in the form of a formula the eminrical results presented 

 in the above paper. 



Inbreeding and relationship coefficients, R. Pkarl (Amer. Nat., 48 (1914), 

 No. 573, pp. 513-523, figs. 2). — In this paper the author calls attention to the 

 fact that '* an individual may be inbred in 10 generations to within 0.2 per cent 

 as intensely, measured by the coelficieuts of inbreeding, if his sire and dam are 

 in no way related, as he would be if his sire and dam were brother and sister." 



A method is presented for measuring separately what proportion of the ob- 

 served inbreeding in a particular case is due to kinship of the parents, and what 

 to earlier ancestral relationship. A proposed coefficient of relationship is de- 

 scribed and its ap])lication illustrated by concrete cases. 



Formulas for the results of inbreeding, II. S. Jennings (Amer. Nat., 48 

 (1914), No. 575, pp. 693-696) .—The author exiwnds the work of Pearl (see 

 above) on the results of inbreeding. A general formula is presented for the 

 rate at which organisms become homozygotic through continued brother by 

 sister mating. This consists in "(1) the proportion of individuals that will be 

 homozygotic for any given character after any number of unbroken generations 

 of such inbreeding, (2) the average proportion of the characters of a given in- 

 dividual that will be homozygotic after any number of unbroken generations of 

 such inbreeding. The numerical value so obtained may conveniently be called 

 the coefficient of homozygosis." 



The rule is expressed as follows: " The value of the coefficient of homozygosis 

 X for any term (as the nth) is obtained by doubling the numerator and denomi- 

 nator of the fraction expressing the value for the previous term, and adding to 

 the numerator the corresponding (n-lth) term of the Fibonacci series." 



Valuation of feeding stuffs by means of chemical analysis, A. Smetham 

 (Analyst, 39 (1914), No. 464, pp. 481-491). — ^Analyses are reported of a number 

 of English feeding stuffs including a number of unusual products from India, 

 Egypt, Brazil, and other places. 



The influence of the phosphate and potassic fertilizing of meadows on the 

 chemical composition of the forage, C. Dusserre (Ann. Agr. Suisse, 14 (1913), 

 No. 4< PP- 271-273). — In experiments to determine the influence of phosphatic 

 fertilizing on the composition of grasses, it was found that the phosphorus con- 

 tent was materially increased when phosphorus was added to the meadows iu 

 the form of superphosphate. 



Studies on the various straws with reference to the crude fiber content 

 and the composition and digestibility under the influences of weathering, F. 

 HoNCAMP, P. Ries, and H. Mullner (Landw. Vers. Stat., 84 (1914), No. 5-6, 



