9 6 



HISTORY OF THE HUMAN BODY 



of amphibians, owing to a similarity in the early stages of 

 development; but although this view may receive some little 

 extra support from the considerable degree of sensitiveness 



FIG. 26. Development of hair. 



sir. c, stratum corneum; str. muc., stratum germinativum; seb, sebaceous gland; 

 fol, follicle; out, outer root sheath; in, inner root sheath; G, hair germ; d, beginning 

 hair; pap, corium papilla. 



which some hairs attain, the evidence in favor of it is slight, 

 and the idea does not receive general credence. It seems 

 likely that the hair developed subsequently to the scales and 



