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through the dorsal trunk musculature and then almost directly 

 laterally. Before uniting with the third nerve it supplied several 

 branches to the abdominohyoideus musculature. No union was 

 found between the ventral rami of the first and second nerves. 

 The former was found to pass somewhat caudally, then laterally, 

 terminating in the posterior segments of the m. sternohyoideus. 



Fig. 12 Graphic reconstruction of the segmental nerve contribution to trans- 

 planted limb in case AA2S21 (fig. 11). X 25. Arrow designates level of trans- 

 planted limb. 



Fig. 13 Graphic reconstruction of the segmental nerve supply to trans- 

 planted limb in case AA2S24. Limb, transplanted into the gill region (fig. 2), 

 has migrated caudally during development, finally occupying a position approxi- 

 mately one segment anterior to the normal position. X 25. Arrow A indicates 

 position of transplanted limb; arrow B designates normal limb level. 



A typical anterior prolongation of the hypoglossal nerve was 

 lacking in this case, as were also the anterior segments of the 

 m. sternohyoideus and their derivatives (m. geniohyoideus and 

 m. genioglossus) . 



Case AAIS24. Although in this experiment the limb rudiment 

 was transplanted into the gill region, as is indicated in figure 3, 

 its final position was only one segment anterior to the normal, 



