6. The extension of the entoderm basis is almost the same 

 up to the 2-cell stage, that of the 4-cell stage not having been 

 determined. 



7. 4-, |- and f-embryos are all alike and almost normal, 

 assuming the shape of young pilidia. -^-embryos are abnormal, the 

 shifting of the apical organ to one side being found in some cases. 

 In some of the l-embryos the apical organ fails to develop. 



8. Bilaterality of egg-substances" can not be detected at the 

 4-cell stage. 



9. 4-embryo may be perfect. 



10. At the 8-cell stage, if the horizontal cleavage is made 

 to cut along the equator, the upper quartet always produces an 

 aneuterion, while the lower one develops into a larva thick walled, 

 invaginated and devoid of the apical organ. If, however, the 

 third cleavage plane is below the equator the result may be 

 variable. 



11. The group of two animal cells and one vegetal cell of the 

 8-cell stage (2A+lV)may develop into a perfect pilidiuni. 



12. In bisecting horizontally blastulus and young gastrulas, 

 the pilidia from both the upper and lower halves may acquire 

 the apical organ. 



13. If the apical organ be cut off after late gastrula or young 

 pilidium stage, it may be found regenerated in the advanced 

 pilidium stage. 



14. If the cleavage pattern be modified either by pressure 

 or by Ca-free sea-water (ring- and plate-embryos) the resulting 

 larvae always have some abnormal features, yet in a general way 

 they take the form of pilidia. 



8 The lU must be localized in one ol" tlie cells. This cüiiclusiun muy, therefore, be 

 applied only to other substances. 



