Text-fig. 5. 



Egs seen from the vegetative pole at a later stage. M has 

 divided to give rise to the paired mesoteloblasts M and 3/'. 



Text-fig. 6. 



Optical section of an egg at a somewhat later stage at the level 

 of the mesoblasts, seen from the vegetative pole. The two 

 cells, M and M^, have each given rise to a small anterior 

 mesoderm cell, m and mK 



