DISEASKS OF POULTRY 



145 



Fig-. 34. Fig. 35. F iff. 36. 



Fijr. 34. — EtrfT from upper part of oviduct with coating- of dense albumen 

 called membrana chalazifera continued into the clialaz;e. Fig-. 35. — Out- 

 stretched chalaz.e from opposite sides of the yolk showing <>p])osite turns 

 of the spiral. Fig. 36 — Egg from above middle of oviduct with tirst la.vers 

 of soft albumen. 



upper portion of the oviduct and soon after the egg 

 escapes from the ovary. Having entered tlie oviduct 

 the ovum is propelled with a rotarj^ motion by the 

 peristaltic contractions of that tube, towards th.e 

 cloaca. The contact of the ovum stimulales the lin- 

 ing membrane of the oviduct to secrete first a dense 

 laj-er of al])umen which is deposited upon the vitelline 

 membrane and is continued thread -like from each pole. 

 These threads or filaments are the chalazce and the 

 dense layer of albumen with which they are connected 

 is the incmbrana chalazifera. As the ^"g^ rotates in 

 the oviduct the chalazce become twisted in opposite 

 directions, and the one next the small end of the ^g?, 

 finally adheres more or less to the membrane lining 

 the shell at that point. 



