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ALBERT KUNTZ 



limiting membrane. The vagus ganglia at this stage appear as 

 elongated cell-masses which are not sharply limited distally. Cells 

 apparently become separated from their distal ends and migrate 

 peripherally along the paths of the vagi. As far as the latter may 

 be traced peripherally they are accompanied by numerous cells 

 many of which become separated from the vagus trunks and become 

 distributed in the walls of the digestive tube to give rise to the 

 myenteric and the submucous plexuses, or wander into the an- 

 lagen of the other vagal sympathetic plexuses. 



ElM. V^^.R 



M. \4y.R. 



Fig. 13 Sections through vagus rootlets in an eleven-day embryo taken at 

 different levels. X 350. E.L.M., external limiting membrane; Vag.R., vagus 

 rootlets. 



It may be of interest to note at this point that embryos of the 

 turtle afford exceedingly satisfactory preparations for the study 

 of the development of the vagal sympathetic plexuses. The cells 

 constituting the anlagen of these plexuses are exceedingly numer- 

 ous and respond readily to differential stains. In well stained 

 preparations the cells giving rise to these plexuses can be traced 

 from the vagus trunks with such certainty that there can be no 

 doubt as to their genetic relationship. Furthermore, cells can- 

 not be traced into the anlagen of these plexuses, except in the 

 posterior region of the intestine, from any other source until they 

 have become well established. These observations do not pre- 

 clude the possibility that a few cells may be transferred from 



