FIG. 288. Eighteen hours FIG. 289. Second day FIG. 290. Forty hours 



FIG. 291. Third day FIG. 292. Fourth day FIG. 293. Fifth day 



FIG. 294. Fertile egg seen FIG. 295. Fertile egg, FIG. 296. Chick just be- 

 through tester, seventh day fourteenth day fore hatching 



DEVELOPMENT OF CHICK IN INCUBATION 



(Photographs from E. T. Brown, made by E. C. Hearson, London, England. 

 Figs. 288-293 and 296 show contents of egg with shell removed) 



261 



