J. BOEKE. On Gastrulation and the covering of the yolk in the teleostean egg. 



PLATE 2. 



Fig. la. 



'EJC 



Fig. 16. 



Fig. \e. 



Fig. lc. 



Fig. 2a. 



Fig. 26. 



Fig. 2c 



Fig. 2d. 



Fig. 3. Fig. 4. 



J. Boeke del. 



Proceedings Pioyal Acad. Amsterdam. Vol. IX. 



