THE REPRODUCTIVE ORGANS 73 



of egg,^^ in which are two twisted cords or 

 chalazce (so named from their supposed re- 

 semblance to hailstones), generally regarded 

 as produced by the rotation of the egg as it 

 passes down the oviduct. 



Four layers of albumen have been dis- 

 tinguished, (a) The thin chalaziferous layer is 

 dense and lies next to the yolk at the poles 

 of which it is continuous with the chalazse. 

 (b) An inner layer of fluid albumen has been 

 described as surrounding the chalaziferous 

 layer, but Dr. Raymond Pearl and Miss Curtis 

 cast doubt upon its existence, (c) The bulk 

 of the " white of egg " is formed of dense 

 albumen, consisting of a close network of 

 interlaced, dense albumen fibres, with fluid 

 albumen in the meshes, (d) Finally, the outer- 

 most layer of the " white " consists of fluid 

 albumen. 



The yolk of the egg, surrounded by a thin 

 vitelline membrane, is not homogeneous but 

 is composed of yellow and white material. 

 The white yolk forms a flask -shaped mass, 

 centrally placed, and thin concentric layers 

 separating thick layers of yellow yolk. Both 

 white and yellow yolk are composed of small 

 spherules or granules unseparated by any 



