368 THE SKIN AND THE SENSE-ORGANS. 



According- to Pfitzner these cells secrete a substance, which has 



Fig. 229. 



P P 



Vertical seotion througli tlie skin of the back ; after Wiedersheim. 



Co Superficial layer of cutis. 



Co^ Middle layer of cutis. 



Co'^ Deep layer of cutis. 



Z) Cutaneous glands. 



iA Uucts of cutaneous glands. 



Ep Epidermis. 



H Horny layer of epidermis. 



P Pigment-cells. 



W Papillae. 



an important function in connection with the process of easting- the 

 skin, which consists in the separation of the upper layer from that 



Fig. 230. 



Fig. 231. 



JkC 



Surface view of epidermis of Rana tcmporarla ; Nerve terminations in the branched pigment-cells 



after Ebertli. of the cutis; after Ehrmann. Hartnack, Obj. 



A Epidermal cell. ' ' ^' 



li Stoma-ceU. I. Pigment ceasing abruptly at junction of 



C Attached cuticle from duct of gland, nerve. 



i> Protoplasm and nucleus of stoma-ceU. II. Pigment gradually ceasing along the nerve. 



below brings about a complete shedding of the skin (Wiedersheim). 



