REGENERATION IN VERTEBRATES £87 



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Figure 2. Electron micrograph of two epidermal cells near tip of late regen- 

 erate bud. Note the fuzzy accumulation, precursor to the adepidermal mem- 

 brane, adhering to the underside of the cells. A long fragment of fully formed 

 adepidermal membrane can be seen at the lower left, and small bits through- 

 out. Fixation: osmium tetroxide. Magnification: approximately 17,500 X. 



size of the intercellular space varies greatly in the epidermis of the 

 regenerate but not in that of normal skin, where adjacent cellular 

 boundaries follow one another closely with only a minute space be- 

 tween. In some regions of the regenerate the space is as small as that 

 for normal epidermis. In other regions the cellular spaces are many 

 times greater, are more irregular in contour, and adjacent borders only 

 loosely follow one another, although bridges are maintained between 

 the two with their characteristic fine structure. Enlarged intercellular 

 spaces are observed in all layers of the epithelium except in the outer 



