SYMPATHETIC GANGLIA 249 



ing from the ophthalmic nerve may be traced into the anlage of 

 the cihary ganghon (fig. 12, rl). The fibers of this ramus are ac- 

 companied by nmnerous nervous elements which have advanced 

 peripherally from the Gasserian ganglion along the fibers of the 

 ophthalmic nerve. Many of these cells enter the anlage of the 

 ciliary ganglion. At this stage of development, however, the cil- 

 iary ganglion is already well established. It, therefore, arises 

 primarily from cells which advance peripherally from the mesen- 

 cephalon along the oculomotor nerve but later receives cells also 

 which wander out from the Gasserian ganglion along the ophthal- 

 mic nerve. 



As development advances, the cells in the anlage of the cil- 

 iary ganglion become more numerous and more compactly ag- 

 gregated. The ganglion, however, remains closely associated 

 with the oculomotor nerve. 



Observations on the development of the ciliary ganglion in 

 embryos of Chelydra agree in all essential respects with the 

 observations on the development of this ganglion in Thalasso- 

 chelys above recorded. 



SpeMopalatine ganglion 



The sphenopalatine ganglion arises, in embryos of the turtle, 

 ventral and somewhat mesial to the path of the maxillary nerve. 

 In embryos of Chelydra 11 to 13 mm. in length, the anlage of 

 this ganglion appears, in sagittal sections, as an elongated aggre- 

 gate of cells in the path of the great superficial petrosal nerve and 

 connected with the maxillary nerve by one or more slender rami 

 (fig. 15, sph g). 



In early embryos of both Thalassochelys and Chelydra, the great 

 superficial petrosal nerve may be traced from the geniculate 

 ganglion into the maxillary region as a relatively large nerve 

 whose fibers are accompanied by cells obviously of nervous origin. 

 Near its proximal end this nerve is joined by fibers which emerge 

 from the sympathetic plexus surrounding the carotid artery. It 

 is not impossible that cells advancing cephalad from the superior 



