563 



region. But so far as the faintly marked encephalomeres of the re- 

 gion can be followed they point to the number being five. There are, 

 as has been said, three somites left with their ventral roots, and the 



Fig. 3. Kabbit. Sagittal section through rhombomeres 2 — 7. The infundibulum, 

 hypophysis, and Seessel's diverticulum are also shown, below rhombomeres 2 and 3. 



Fig. 4. Eabbit. Sagittal section through lateral region of hind brain, showing 

 rhombomeres 1—4, ganglion VII— VIII, and Auditory vesicle. 



36* 



