HYPOGLOSSAL GANGLIA OF PIG EMBRYOS 



275 



from the first cervical to the jugular ganglion. In fig. 7, the first 

 cervical ganglion is double. Froriep's ganglion is independent 

 of the rudimentary crest and shows two proximal roots, one con- 

 necting with a small lateral spur. The distal root is large and 



gang hypoql 

 qonq Froriep 



mijelencephalon 



HE. 



qanq 

 nodos. 



Fig. 7. Dissection of an IS mm. pig with three distal roots passing from the 

 hypoglossal ganglia to the ventral roots of the hypoglossal nerve. The first cervi- 

 cal ganglion is double and the neural crest is persistent from the first cervical 

 to the jugular ganglion. 



its fibers join the caudal root of the hypoglossal some distance 

 ventral to the spinal cord. Next anterior are three connected 

 masses of ganglion cells which increase in size cephalad. Two 

 proximal and two distal roots are seen. The distal roots are ex- 

 tremely small and it is doubtful whether their fibers enter the 



