HYPOGLOSSAL GANGLIA OF PIG EMBRYOS 



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middle of the hypoglossal chain, that is, about midway between 

 Froriep's ganglion and the jugular ganglion. 



Stage 6. 41-50 mm. Two dissections showed conditions 

 similar to the preceding. A double Froriep's ganglion was found 



qanq. hijpoq 1 

 qanq.Froriep 



qanq. sup. 

 qanq.juqul 



_A qanq.petros. 



Fig. 8. Dissection of a 28 mm. pig showing Froriep's ganglion and a distal root 

 to the hypoglossal nerve. The middle portion of the series of hypoglossal ganglia, 

 present in earlier stages, has disappeared. 



in one case relatively smaller than in the embryo of 30 mm. 

 Its arrested development was shown by its unchanged position 

 and small size. It lies still partly dorsal to the spinal accessory, 

 while the cervical ganglia have shifted ventrad owing to the 

 elongation of their roots, and to their own growth. 



