Fig. 7 Dorsal view of model of mesoderm (white), mesenchyme (green), 

 vasofactive cells (yellow) and endothelium (red) of an embryo of eight somites. 

 Columbia collection No. 530, X 300. Reduced \. 



1 Somite 1 4 Region of cardiac coelom 



2 Anlages of juxta-neural anastomosis 



3 Connection of juxta-neural anasto- 



mosis with the aorta 



62 



