260 



Human Physiology. 



new being, insect, bir,d, or man, with the same wisdom and 

 power that creates a universe. 



The first step in development in the yolk of the egg must be 

 the vitalisation of its matter further vitalisation, I should say, 

 for it is already alive an organised existence. But the entrance 



Fig. 66. CHICKEN'S EGG, THIRD DAY OF INCUBATION. 



of the masculine element or its union with the feminine ele- 

 ment, whatever they may be gives a new and. very intense 

 life. There is a diffusion, perhaps a rapid spreading growth of 

 fibres of the nerves of organic life. Under their influence cells 



brane of the shell, which, at d, d, splits into two layers. *, t. Limits of the 

 second and thicker albumen, f. Limits of the third and thickest albumen, the 

 white being in three layers, g, . Chalaze, or ropes of twisted fibres from 

 the yolk, which hold it in its place, h. Yolk. /. Central cavity in the 

 yolk, from which a duct, k, leads to the cicatricula, or tread. /. Cumulus 

 proligerous, or germinal cumulus, nt. Germ, or blastos. The egg is so 

 formed that the yolk floats high in the white, and the germ is always upper- 

 most. 



