NEURAL CANAL 



343 



per, and the extra-embryonic accessory structures, the um- 

 bilical vesicle, amnion, allantois and placenta. As regards 

 the embryonic body, some of the most prominent occurrences 



connected with its development consist in the formation of 

 the neural canal, chorda dorsalis, or notochord, and meso- 

 blastic somites. 

 Neural Canal. About the fourteenth day, along under- 



