1927 Felix Pinkus

 
Entwicklungsgeschichte der Haut. In: Jadassohn J (ed). Handbuch der Haut und Geschlechtskrankheiten. Berlin: Erster Band Erster Teil, Springer, 1927;111-378 (Figs. 6 & 7).

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Fig. 6  [Fig. 172] Very prominent epithelial outgrowth in the bulge region of the hair follicle. Attachments of the m. arrector pili to the outgrowth. Some of them are completely surrounded by muscle. (Reproduced with permission.)

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Fig. 7  [Fig. 226] Pubic hair, lanugo hair, sebaceous glands, m. arrector pili, epithelial outgrowth in the area of the muscle attachment (bulge), hair shaft, opening for the papilla. (Reproduced with permission.)
 

Message

 
F. Pinkus restates Garcia"s position, namely, that the cells beneath "the bulge" are responsible for formation of a new follicle, whereas "the bulge" itself is simply the site of attachment for the hair arrector muscle.
 
"The bulge" is situated at the lower end of the permanent segment of the follicle.
 
Drawings of the upper segment of follicles in cross section show "the bulge" is actually bulges.
 
The several epithelial outgrowths of "the bulge" that serve as sites of attachment for the musculus erector pili sometimes house whorls of cornfied cells ("horn pearls") and represent the anlage of rudimentary follicles.
 

Critique

 
F. Pinkus ascribed the source of cells responsible for a new follicle to the base of the isthmus and not to "the bulge," a judgment with which we concur.
 
F. Pinkus defined "the bulge" correctly histologically, to wit, protuberances from the lower part of the permanent segment of a follicle, i.e., the isthmus.
 
The drawing pictured bulges as tubular, but, in reality, they are solid.
 
The nature of the outgrowths that house whorls of corneocytes, which Pinkus regarded as anlage of rudimentary follicles, has yet to be deter-mined convincingly.