SYMPATHETIC NERVOUS SYSTEM IN MAN 203 



the pig any cells enter the submaxillary ganglion from sources 

 other than the semilunar ganghon. 



In keeping with his conclusion that the sphenopalatine and 

 otic ganglia are derived exclusively from cells which advance 

 peripherally along the greater superficial petrosal and the lesser 

 superficial petrosal nerves, respectively, Stewart ('20) has con- 

 cluded that the submaxillary gangUon arises exclusively from 

 cells which advance peripherally along the chorda tympani. In 

 view of the intimate relationship of the primordium of the 

 submaxillary ganglion with the lingual nerve, he admits that 

 direct observations can lend little support to this conclusion. 

 Obviously, however, it is demanded by the theory that these 

 several ganglia rise exclusively from cells which advance periph- 

 erally along the nerve trunks which later carrj?^ the preganglionic 

 fibers to each ganglion respectively. 



Sublingual and lingual ganglia 



As the lingual nerve grows distally beyond the primordium 

 of the submaxillary ganglion, as observed in embryos 12 mm. and 

 over in length, its fibers are accompanied by numerous migrant 

 cells. Some of these cells have become aggregated in the path 

 of the nerve to give rise to the sublingual ganglion, while others 

 advance along the branches of the lingual nerve to give rise to 

 the smaller ganglionic masses in the tongue which remain asso- 

 ciated with the lingual rami. Obviously, the larger sublingual 

 ganglion and the smaller ganglionic masses associated with the 

 rami of the lingual nerve arise from cells whose sources are essen- 

 tially the same as those of the cells which give rise to the sub- 

 maxillary ganglion. 



The small sympathetic ganglia in the posterior portion of the 

 tongue arise in association with the lingual ramus of the glosso- 

 pharyngeal nerve. During the early developmental stages this 

 nerve also contains cells of cerebrospinal origin. As the lingual 

 ramus grows into the tongue aggregates of cells occur near its 

 growing extremity (fig. 11, SLG). Some of these cell-groups 

 remain closely associated with the nerve trunk, while other cells 



