Fig. 7 Dorsal view of inodpl of mesoderm (white), mesencliyme (green), 

 vasofactive cells (yellow) anil endotlielium (red) of an embryo of eight somites. 

 Columbia collection No. .5.30, X 300. Reduced i 



1 Somite 1 4 Region of cardiac coelom 



2 Anlages of ju.xta-neural anastomosis 



3 Connection of juxta-neural anasto- 



mosis with the aorta 



62 



