II 



NKUVK DEVELOPMENT 



109 



Fie. 60A. Portions of transverse sections through young Lt'piiloshvns to illustrate 

 the development of the spinal nerves (ventral roots). 



B. si.-t-f -_':. ; ( ', si. -I-.- -J7. in, myotome ; n, nerve-trunk ; >-.c,| r spiiial con! ; s/i, sheath 



