68 ART. 3. S. 1KEDA : CONTRIBUTIONS 



the closing point of the blastopore was at or near the 

 punctured point, and the anterior § or | of the embryonic 

 body were formed in front of the point at which the dorsal 

 lip first appeared. 



Egg No. 3. 



April 23, 4:15 p.m. : — Taken from another egg-mass and punctured at 

 the upper pole, as in Group IV., No. 9. Fluid contents of the 

 segmentation cavity forcibly ejected, and the upper hemisphere 

 shrunken. After a few minutes ejection stopped. 



April 24, 7:25 a.m. : — Shrinkage of the upper hemisphere recovered, 

 although the area of the segmentation cavity unusually small. 

 Blastopore circle completed and grown down to about 50° 

 below the equator. Neural plate faintly visible. 

 2:20 p.m. : — Small ex-ovate found in front of the neural plate and 

 to the right of the median line. 



April 25, 5:00 p.m. : — Blastopore completely closed. General outline 

 of the embryonic body evident, with well-defined neural groove 

 and folds. Ex-ovate found 20°-50° forward from the head- 

 end of the embryo, about opposite the final closing point of 

 the blastopore. Embryo quite normal. 



This egg was therefore like Group IV., Egg No. with this 



difference, that in the latter the embryo was shorter, owing to the 



exudation of the large secondary ex-ovate after the first was lost. 



Egg No. 4. (Figs. SU a-c, Fig. ( J0). 



April 23, 8:20 + a.m. : — (Fig. a). Punctured on both sides of the dorsal 

 blastopore lip, some distance below its level (us in the eggs 

 of the corresponding number in Groups I., and IV.). In this 

 egg, left puncture at the periphery of the egg when seen in the 

 posterior view ; right puncture higher and nearer the dorsal lip. 

 2:40 p.m. : — (Fig. b). Dorsal lip grown downwards and elongated, 

 left limb reaching the left ex-ovate ; right limb slightly above 

 the right ex-ovate. 



April 24, 7:00 a.m. : — (Fig. c). Blastopore lips grown further down- 



