272 



C. W. PRENTISS 



Froriep's ganglion sends fibers to the hypoglossal at an earlier 

 stage than has been described by other investigators; (3) its 

 resemblance to one of the divisions of the first cervical ganglion 

 is marked. 



/ 



qang. hypogl 

 gang Froriep 



nod. 



rmjelencephalon 



qanqsup 

 qang.jugul 

 "Z EC 



Fig. 5. Dissection of a 13 mm. pig showing a scries of eight hypoglossal ganglia 

 and the persistence of the neural crest from the superior ganglion to the first cer- 

 vical. 



Stage 3. 13 mm. This embryo, of about the same age as that 

 studied by Lewis, is characterized by a further elongation of the 

 distal and proximal roots and by a greater differentiation of the 

 neural crest anterior to the first cervical nerve. Five of the ten 

 embryos dissected belonged to the types shown in fig. 4 and fig. 

 5. Here we see a cord of cells passing cephalad from the first 

 cervical ganglion. In fig. 5 it joins Froriep's ganglion. In fig. 4 



