1958 Hermann Pinkus

 
Embryology of hair. In: Montagna W, Ellis RA (eds). The Biology of Hair Growth. New York: Academic Press 1958:1—32.
 

Message

 
The isthmus is situated between the bulge and the sebaceous gland.
 

Critique

 
H. Pinkus did not describe the boundaries of the isthmus accurately; it is bounded by the sebaceous duct above and by desquamation of cells of the inner sheath below. "The bulge" cannot be a boundary of the isthmus because bulges are components of the isthmus, i.e., protrusions from the lower part of it.