36 



CYTOMORPHOSIS 



form the leaf. Later the cells degenerate and die. The leaf 

 becomes dead and falls. It would be easy to lay before 



Hor.La J 



Fig. 21. 



Fig. 21. — Cytomorphosis of the cartilage cells. From a section of the vertebral 

 arch of a pig embryo, a-e, successive stages; in e, the letters kn refer to the limit of 

 the cavity which is no longer filled by the degenerating cell. 



Fig. 22. — Epidermis from the sole of the domestic cat. Ba. Schi, basal germ 

 layer; Eor. La, hor. i, hor. z', horny layer formed by dead cells; ker. k, layer of cells 

 which are being comified; Ml. La, middle layer of cells which are migrating upward 

 and at the same time enlarging; Pa, site of a hypodermic papilla. — After K. A . Schnei- 

 der. 



