Gcortre L. Strccter 



95 



Embryos of Ahout Tliirti/ Days. 



Mall Collection, No. 114 10.0 mm. 



His Collection, Embryo Dl 10.0 mm. 



His Collection, Embryo KO 10.3 mm. 



(See Fig-s. T, 8, 9 aiul 14.) 



On coming to embryos 1.0 cm. long the final steps in the transforma- 

 tion of the occipital ganglion crest into cranial nerve rootlets and their 

 ganglia may be seen. When Figs. 7 and 8 are compared with Fig. 4, a 

 considerable increase in the actual mass of cells is observed in this region, 

 and also a marked growth of the fibre elements. As this fibre formation 



ory va9u5 



Rad . dors. 



Interganglionic 

 ■bridge 



Fig. 9. Heconstruction of peripheral nerves in thirty-one days human embryo, 10.0 ram. 

 long. His collection Embryo Dl. ^Enlarged lfl.7 diams. 



