TRANSPLANTING NEURAL TUBE OF AMBLYSTOMA 



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planted tube can be clearly seen, but as the section passes lateral 

 (left) to the brain and cord of the host, none of the latter can be 

 seen. It is evident that the transplant has progressed in its 

 development, having closed completely and having grown in 

 thickness and length. The section shown in C passes nearer to 



Fig. 3 A, embryo T.L.I; B and C, sagittal sections, 

 neural tube. Eight days after operation. 



t.n., transplanted 



the midline. It shows the transplant and both stumps of the 

 neural tube with the transplant in close contact with the anterior 

 stump. At first glance, it might appear that these two regions 

 had fused, but a closer examination under higher power (fig. 4) 

 shows that this is not the case, and that the cells of the two 

 regions are rather sharply marked off. The condition was brought 



