60 A&T. 3. — S. IKEDA : CONTRIBUTIONS 



being thereafter undertaken by the dorsal and lateral lips. The 

 location of the embryo must therefore be, as in Fig. 84, on the 

 lower hemisphere of the egg. The results are exactly as in Egg 

 No. 5, the only difference being that, as the puncture was further 

 down in this egg, the position of the embryo was different in the 

 same degree. 



First Group. (Figs. 85-86). 



The eggs of this group were picked out from a mass obtained 

 on the morning of April 17th., (deposited in all probability on 

 the morning of the 16th.) and were at the time at the end of the 

 segmentation process. The first trace of the dorsal blastopore lip 

 appeared at 2 p.m., of the same day. Puncturing was begun at 

 2:30 and finished at 4:40 p.m. 



Egg No. 1. 



April 17, 2:30 p.m. : — Punctured at the approximate center of the 

 lower yolk hemisphere as in Group IV., Egg No. 1. {Cf. 

 Figs. 67 rt-e). Watched until April 19, 2:12 p.m. when the 

 embryo had been completely formed in the normal way, with 

 only the ex-ovate attached to the distal end of the embryonic 

 body. Eesults are exactly as in the egg referred to : hence 

 details may be omitted. 



Egg No. 2. 



April 17, 2:30 -f p.m. : — Punctured below the dorsal lip slightly to the 

 left of the median line, at a point which was two-thirds of 

 the distance from the yolk polo to that lip (as in Group IV., 

 Egg No. 2, Figs. 68 «-/'). Puncture unfortunately rather 

 severe and an excessive amount of egg-contents exuded. 



April 18, 2:00 p.m. : — Upper hemisphere strongly depressed. Area of 

 the segmentation cavity vanished. Still more matter exuded 



