50 



Fig. 5 



Fig. 6 



Fig. 4 A, Bias-cut strip of tissue from the periphery of a Cassiopea disk. Regenerating tissue 

 stippled. SO, sense organs. B, the form assumed by the strip A, its nearest approach to the original 

 disk-shape. 



Fig. 5 A, V-shaped portion of the Cassiopea disk, regenerating along the cut edges. B, a pulsat- 

 ing cup-hke body formed by the V-pattern and its newly regenerated tissue. 



Fig. 6 A, an equilateral triangle cut so that one of its sides contains sense organs from the Cassiopea 

 disk border. B, the pulsating cup-shaped body formed by the triangle. Angles a-a are brought to- 

 gether and the apex c forms the base of the cup. Regeneration in all of the preparations stops when 

 the circular form is completed. 



