The Early Devclopiiieut of the Pigeon's Egg, 



57 



Fig. 47. — I'hotograpli of pigeon egg at 2.30 a. ni., aliout six and one-half 

 hours after fertilization. Killed and photographed in 5 per cent formalin in 

 normal salt solution. Notice the vacuoles in the yolk surrounding the blasto- 

 derm. 



