164 



POULTRY PRODUCTION 



which is prolonged toward the large and the small ends of 

 the egg, respectively, in two whitish, convoluted strands 

 called chalazse (Fig. 76). The two chalazse are twisted in 

 opposite directions. The Ime describing the long axis of 

 the egg will pass through the bases of the two chalazse and 

 be at right angles to the axis of the yolk passing through 

 the center of the blastoderm. 



Surrounding and continuing this dense albumen is a spiral 

 layer of somewhat less dense albumen which is in turn 

 surrounded by a thin, watery albumen. The difference be- 



FiG. 76 



Blastodelrm 



Cuticle 



5hell 



Outer Shell Membrane 

 Air Ce.ll 

 Chalaza 



NNER Shell Membrane 

 Dense Albumen 

 Liquid Albumen 



Dark Yolk 

 — White Yolk. 

 Vitelline Membrane 



Parts of an egg. 



tween the dense and thin albumen is easily noted when a 

 new-laid egg is broken into a saucer."^ The spiral formation 

 of the albumen may be noted by carefully dissecting the 

 "white" of a hard-boiled egg. One of the functions of the 

 albumen is to prevent microorganisms from reaching the 

 germ spot. To this end it has marked bactericidal propierties. 

 Once in the yolk, bacteria are safe, for the yolk has no defen- 

 sive properties. The shell membrane consists of two layers, 

 a thick outer layer next to the shell and a thinner one next 

 the albumen. Both are composed of matted organic fibers 



' See Fig. 226, page 470. 



