ANIMAL PRODUCTION. 271 



whereby It becomes more absorbent. This Influence can b« overcome by cover- 

 ing the wooden parts with oiled cloth. 



Report of proceedings of the conference on the poultry industry, Dublin, 

 May, 1911 {Dept. Agr. and Tech. Instr. Ireland, Conf. Poxiltry Indus. Proc, 

 1911, May, pp. yiII+23-i). — Besides statistics on poultry and other matters 

 relating to the poultry industry in Ireland this contains the following papers: 

 Education in Poultry Keeping in Ireland, by J. R. Campbell; Promotion of 

 Poultry Keeping, by E. Brown and P. A. Francis; Production of and Trade in 

 Table Poultry, by F. B. Nasmyth-Miller- and J. W. Hurst; Transit of Eggs and 

 Live Poultry, by D. S. Prentice; Present Position and Needs of Cooperative 

 Collection and Distribution, by J. N. Harris; The Organization of the Irish 

 Poultry Industry, by R. A. Anderson ; Collection and Grading of Eggs, by J. 

 Drysdale and T. S. Porter ; and Sale of Eggs, by P. Hickey and L. Wilson. 



Plans and descriptions of five-acre poultry farms and the addresses of 

 the lecturers at the State Poultry Institute, edited by T. E. Quisenberry 

 (Mo. Poultry Bd. Quart. Bui, 1 {1911), No. 2, pp. 133, figs. 67).— This treata 

 of different phases of the poultry industry. The articles are contributed by 

 several authors. 



Studies on the early development of the hen's egg-. — I, History of the 

 early cleavage and of the accessory cleavage, J. T. Patterson {Jour. Morph., 

 21 {1910), No. 1, pp. 101-134, figs. 32).— Ovulation is thought to be directly 

 caused by the activity of the infundibulum. As in the case of the pigeon, fertili- 

 zation took place immediately after ovulation, when the egg was in the region 

 of the infundibulum. Only 5 or 6 supernumerary sperm nuclei entered into the 

 egg except in one case. Upon their entrance into the egg each migi*ated toward 

 the periphery of the disc, some of them passing down to the deeper portions to 

 undergo a complete fragmentation, while others reached the margin, giving 

 rise to a rudimentary accessory cleavage, which disappeared shortly after the 

 8-celled stage, or between 4 and 5 hours after fertilization. 



The period of development from the first cleavage until the 346-celled stage 

 was reached was estimated to be about 8 hours. Under normal conditions it 

 takes about 22 hours for the egg to traverse the entire length of the oviduct. 

 The time occupied in the different portions was as follows : Glandular portion 

 3 hours, isthmus 2 to 3 hours, uterus and laying 16 to 17 hours. It was found 

 possible to lengthen the time beyond 22 hours by disturbing the hen when 

 about to lay. On one occasion it was delayed for 20 hours, and when it was 

 finally deposited and examined this was found to be equal to about 20 hours of 

 incubation. 



Details of segmentation are given in full and compared with those of the 

 pigeon. Hens which laid daily laid about an hour later each succeeding day, 

 though some hens laid so irregularly that the time could not be predicted. 

 Few hens laid before 8 a. m. or after 4 p. m. 



Experiments on developing chicken's eggs, S. Paton {Jour. Expt. ZooL, 

 11 {1911), No. Jf, pp. 469-Jf72). — The technic employed in detaching a fertilized 

 hen's egg from the shell, so that the successive changes in the developing em- 

 bryo could be watched, is described. There is also a brief notice of the action 

 of several fluids upon the embryo. 



The role of salts in the preservation of life, J. Loeb {Science, n. ser., 3 4 

 {1911), No. 881, pp. 653-665).— It is pointed out that the role of salts in the 

 animal body is less known than that of protein, fat, and carbohydrates. Though 

 salts can not furnish energy by oxidation, yet they seem to be a necessary part 

 of the diet. Experiments made with tissues of vertebrates, eggs of inverte- 



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