TO THE EMBRYOLOGY OF AMPHIBIA. 7b 



is the last-noted peculiarity, the main results are the same as in 

 other eggs which received similar injury : the blastopore closed at 

 the punctured point and the embryo was situated as in the normal 

 course of development. 



Egg No. 10. 



Intended to he punctured as in the eggs of the cor- 

 responding number in Groups I., and IV., but owing to failures 

 in manipulation the results were meagre and not worth re- 

 cording ; there was nothing contrary to what had already been 

 made out in other eggs. 



Third Group. (Figs. 93-96). 



The eggs of this group were taken from the mass deposited 

 probably on the early morning of April 27. The dorsal blastopore 

 lip appeared at 12:30 p.m., April 28. Puncturing operations were 

 performed on them between 12:40 and 1:35 p.m. of the same day. 



Egg No. 1. 



Punctured at the approximate yolk-pole, as in the eggs 

 of the same number in the three other groups. Ex-ovate not 

 large. All went well during the first two days, excepting that 

 at one time the surface of the yolk-hemisphere near the 

 ventral lip had a rough appearance. But when examined 

 8:55 a.m., third day (April 30) a large and oval mass of yolk 

 substance had been protruded outward as a yolk-plug along 

 the dorsal blastopore margin. Original ex-ovate a little out- 

 side of the much reduced blastopore area near its ventral lip. 

 At 5:06 p.m., (the same day) the peculiar yolk-plug had been 

 largely withdrawn within the egg-interior. Blastopore become 

 a small circular spot. Ex-ovate further removed from the 



