106 F. W. STEWART 



rise to the sphenopalatine ganghon. The latter ganglion re- 

 ceives supposedly preganglionic fibers of the facialis and dis- 

 tributes postganglionic fibers to the nasal cavity. One would 

 seem justified in assuming that additions to the ganglion cells 

 of the nasal cavity, should such additions exist, would be essen- 

 tially continuations of the same migration which had originally 

 involved the formation of the sphenopalatine ganglion. It has 

 been shown by the author that such is the case, for instance, in 

 the tongue, where continuation of the migration which gives 

 rise to the submaxillary ganglion results in the formation of 

 certain small lingual ganglia in the anterior portion of the tongue. 



Passing to later embryos, however, fourteen and fourteen and 

 one-half day stages, it has proved impossible to trace cells from 

 the sphenopalatine ganglion, at that age very diffuse, into nasal 

 territory, although the ganglion approaches anteriorly very close 

 to the posterior portion of the olfactory sac. Neither has the 

 study of trigeminus branches been productive of results. The 

 next half-day shows little appreciable change. There is some 

 slight evidence of a spreading forward of cells from the spheno- 

 palatine ganglion toward the hard-palate region beneath the 

 nasal passages. Later embryos have failed to confirm this 

 migration. It in no way might involve intermingling with 

 ganglion cells amid the olfactory fila. There would seem to be 

 no way of checking Hardesty's supposition as to the origin of 

 the ganglion cells of the nervus terminalis. I have followed 

 them forward along the internal carotid nerve and along the 

 great deep petrosal nerve. After the junction of the latter with 

 the great superficial petrosal to form the Vidian, it has proved 

 impossible to distinguish them. In view of a failure to observe 

 a migration of cells of the sphenopalatine ganglion into nasal 

 territory, it would seem that the other possibility, that suggested 

 by Hardesty, is at least in part eliminated. 



Embryos of the fourteen and one-half and fif teen-daj^ litters show 

 marked additions in cells clearly neuroblastic, especially among 

 strands issuing from the vomeronasal organ. It may be of 

 value perhaps to compare at this stage cells of the sphenopalatine 

 ganglion with those situated among the olfactory fila and in the 



