478 DAVENPORT HOOKER 
furnished by the position of the ganglia there, as the tension of ° 
the retrogressing cord would not so materially change the di- 
rection of their long axes. 
Fig. 4 Sagittal section of an embryo killed 4 days after operation. The 
epidermal ingrowth has been entirely withdrawn. The motor connections be- 
tween the two ends of the cord have been established and the sensory nerves are 
beginning their development from the posterior piece. (Embryo VIII 68, 3-18). 
Fig. 5 From the same embryo as the preceding figure. The lettering is the 
same as in figure 3. The motor connection between the two ends of the cord is 
shown. (Embryo VIII 68, 3-15 to 20). 
Numerous, long nerve fibers, in all cases containing neuro- 
fibrillae, are given off from both segments of the cord. They 
pass out of the cut ends from the ventral motor tracts. The 
fibers from each segment of the cord branch freely and inter- 
anastomose with each other and among themselves. Some of the 
nerves from the anterior piece of the spinal cord send branches 
to innervate the first three myotomes behind the cut. The main 
fibers in each case are directed toward the posterior piece. The 
ventral motor fibers from the posterior segment of the cord grow 
