92 ALBERT KUNTZ 



becomes connected, in the course of development, with the facial 

 nerve by means of the chorda tympani. The possibility is not 

 precluded, therefore, that cells which wander out from the genicu- 

 late ganglion and advance peripherally along this communicating 

 branch might be carried into the submaxillary ganglion. In 

 view of the fact, however, that this connection is established 

 comparatively late in the course of development it is quite 

 improbable that cells are contributed to the submaxillary gan- 

 glion from this source. Likewise, it is improbable that any cells 

 are contributed to the submaxillary ganglion by way of its 

 sympathetic root which connects it with the sympathetic plexus 

 on the facial artery. 



CONCLUSIONS 



In a series of earlier papers,^ the writer has shown that the 

 ganglia of the sympathetic trunks and the prevertebral sympa- 

 thetic plexuses arise from cells which have their origin in the 

 spinal ganglia and the neural tube and advance peripherally 

 along the sensory and the motor roots respectively of the spinal 

 nerves. Likewise, the vagal sympathetic plexuses, including pri- 

 marily the myenteric and the submucous plexuses, the pulmonary 

 plexuses and the cardiac plexus, arise from cells which have their 

 origin in the vagus ganglia and the walls of the hind-brain and 

 advance peripherally along the paths of the vagi. The cells 

 which advance peripherally from the cerebro-spinal nervous 

 system along the spinal and the vagus nerves and give rise to 

 the sympathetic nervous system are the descendants of the 'germi- 

 nal' cells of His, viz., the indifferent' cells and the 'neuroblasts' 

 of Schaper. The sympathetic nervous system, therefore, not 

 only bears a genetic relationship to the cerebro-spinal nervous 

 system, but is homologous with the other functional divisions 

 of the nervous system. 



The observations set forth in the preceding pages show clearly 

 that the ciliary, the sphenopalatine, the otic and the submaxillary 



^ See bibliography. 



