196 



FRED W. STEWART 



attention, however, to the closeness of its relation to the great 

 superficial petrosal nerve. Kuntz states that the possibility of 

 a few cells reaching the sphenopalatine ganglion via the great 

 superficial petrosal nerve is not precluded; connection is not 

 made, however, with the latter nerve until the anlage of the 

 sphenopalatine ganglion is well established. On the basis of my 

 own preparations, I have been forced to conclude that the 

 sphenopalatine ganglion is a ganglion of the ramus palatinus VII 

 (the great superficial petrosal nerve) . In view of the discrepancy 

 existent in the findings of Kuntz and myself, I have examined 



Fig. 15 Rat embryo, (gray), 5.5 mm., Zenker's fluid, 

 palatinus VII. Projection drawing, X 500. 



A portion of the ramus 



a large number of early stages in the formation of the spheno- 

 palatine ganglion, in all twenty-seven series. Of these, seven 

 are of pig embryos of favorable stages. The intensely cellular 

 character of the ramus palatinus VII is apparent in 5.5-mm. rat 

 embryos (fig. 15). The main trunk of the ramus ends anteriorly 

 in cell-rich strands. In fourteen-day rat embryos, the nerve 

 trunk, contrary to the appearance of others, such as thehypo- 

 glossus where cell content is apparently restricted to sheath cells, 

 shows toward its growing tip, irregular swellings due to local 

 clusterings of accompanying cells; a considerable extension out- 

 ward toward the trigeminus is generally noticeable (fig. 31); 



