ANIMAL PRODUCTION. 471 



Polygamous Mendelian factors, J. Wilson (Sci. Proc. Roy. Dublin Soc, 

 n. ser., 14 (1914), No. 22, pp. 302-312). — Data are presented which tend to show 

 that the various colors In horses are the result of single polygamous factors. 



Annual report on the administration of the grant for the encouragement 

 and improvement of the light horse-breeding industry for the year 1913—14 

 {Bd. Agr. and Fisheries [London], Ann. Rpt. Light Horse-B reeding Indus., 

 1913-14, PP- 56). — This outlines the general plan for the encouragement and 

 improvement of light horse breeding in England, which consists in the subsi- 

 dizing of stallions to travel at low fees, the providing of brood mares for farmers 

 at a small rental, and the elimination of unsound stallions. 



Growth, of the horse, R. Motlocii (Deut. Landw. Tierzucht., 18 (1914), 

 Ausgabe A., Nos. 50, pp. 529-532; 51, pp. 537, 538, figs. 5).— This is a contribu- 

 tion on the growth and body development of the horse from birth to five years 

 of age. 



Feeding roots to work horses, N. Hansson (Meddel. Centralanst. Forsoksv. 

 Jordbruksomrddet, No. 98 (1914), PP- 16, figs. 2). — Successful experiments are 

 reported in which an average of 13.5 kg. of sugar beets per head per day was fed 

 to work horses for from 50 to 89 days with a resulting average daily gain of 0.03 

 kg. per head. Horses receiving 1.5 kg. of grain mixture per head per day under 

 the same conditions lost 0.07 kg. in weight. 



Mendelian inheritance of fecundity in the domestic fowl, and average flock 

 production, R. Pearl (Amer. Nat., 49 (1915), No. 581, pp. 306-317, fig. J).— The 

 author summarizes the material presented in this paper as follows : 



" There is a marked difference in average egg production per bird of Barred 

 Plymouth Rock pullets of the Maine Station strain at the present time as com- 

 pared with what obtained during the period of simple mass selection for this 

 character. This difference is in the direction of a substantially higher mean 

 production at the present time, when tested on flocks of large size. The increase 

 in flock average productivity is most pronounced in respect to winter production, 

 which is the laying cycle to which especial attention has been given in the 

 breeding. The cause of this increase in flock productivity appears, with a degree 

 of probability which is very high and amounts nearly to certainty, to be that 

 the method of breeding the stock now followed is more closely in accord with the 

 mode of inheritance of fecundity than was the simple mass selection practiced 

 in the earlier period. The result announced in earlier papers that high 

 fecundity is a sex-linked character, for which the female is heterozygous, has 

 been confirmed by practical poultrymen in their breeding operations." 



Previous work has been noted (E. S. R., 24, p. 675 ; 28, p. 576). 



Xenia in fowls (Jour. Heredity, 6 (1915), No. 5, pp. 212-218, figs. 2).— This 

 Is a review of recent German work to determine whether a cock has any 

 influence on the color and form of eggs laid by hens to which he is mated. 

 The work of Walther (E. S. R., 32, p. 263) is cited to show that this theory 

 is without solid foundation. 



Studies on the physiology of reproduction in the domestic fowl. — XII, On 

 an abnormality of the oviduct and its effect upon reproduction, Maynie R. 

 Curtis (Biol. Bui. Mar. Biol. Lab. Woods Hole, 28 (1915), No. 3, pp. 154-162, 

 pis. 2). — This is a description of an abnormality of the oviduct of a year and a 

 half old Rhode Island Red hen at the Maine Experiment Station. 



Every possible stage of absorption of the egg from a normal membrane 

 shelled fresh egg to collapsed empty membranes was found. " Some of the 

 eggs and some of the empty membranes were free in the body cavity. Some 

 were partly or entirely inclosed by peritoneum. In several instances two eggs 

 or an egg and a bunch of membranes were walled off together. These peritoneal 

 6318°— No. 5—15 6 



