THE HEN'S EGG. 



[CHAP. 



(Fig. 1, s. m.), and an inner thinner one (i. s. m.). Both 

 of these layers consist of several laminae of felted fibres 

 of various sizes, intermediate in nature between connec- 

 tive and elastic fibres. 



FIG. I. 



ch.l. 



DIAGRAMMATIC SECTION OF AN UNINCUBATED FOWL'S EGG 

 (modified from Allen Thomson). 



bl. blastoderm, w. y. white yolk. This consists of a central 

 flask-shaped mass and a number of layers arranged con- 

 centrically around this. y. y. yellow yolk. v. t. vitelline 

 membrane, x. layer of more fluid albumen immediately 

 surrounding the yolk. w. albumen consisting of alternate 

 denser and more fluid layers, ch. I. chalaza. a. ch. air- 

 chamber at the broad end of the egg. This chamber is 

 merely a space left between the two layers of the shell-mem- 

 brane, i. s. m. internal layer of shell-membrane, s. m. 

 external layer of shell-membrane, s. shell. 



