Cut upon Regeneration in Gunda ulvse. 



357 



takes place at any aboral surface from DD backwards and is independent of 

 the presence of the ganglia. Fragment ABB, or fragments equally small 

 taken from any part of the body, die without any regeneration. 



Fig. I. 



1. Fragment AFF, 14 days ; 2. Ditto, 28 days ; 3. Ditto, 56 days. 4. Fragment AEE, 

 32 days. 5. Fragment BBFF, 14 days; 6. Ditto, 28 days; 7. Ditto, 56 days. 

 8. Fragment DDFF, 14 days ; 9. Ditto, 28 days ; 10. Ditto, 56 days. A. Diagram 

 of points of section. 



B. Lateral Regeneration. 



Animals bisected down the median line (text-fig. II) regenerate completely. 

 The course of regeneration is shown in figs. 1-3. 



In animals beheaded and then bisected down the middle line (fragment 

 PD), regeneration occurs along the edge of the lateral wound, but there 

 is no replacement of the anterior end (text-fig. II, 8-11) unless parts of the 



