SEBACEOUS GLAXDS. 

 Fig. 161.* 



527 



It is this overlapping line that is the cause of the roughness which we 

 experience in drawing a hair from its point to its bulb between the 

 fingers. The bulb is the newly formed portion of the hair : it corre- 

 sponds in figure with that of the pulp, and its expanded form is due to 

 the greater bulk of the fresh cells as compared with the fibres and 

 scales into which they are subsequently converted in the shaft of the 

 hair. 



The colour of the hair, like that of the epidermis, is due to the pre- 

 sence of granules of pigment contained within and among the cells. 



The SEBACEOUS GLANDS are sacculated glandular organs embedded 

 in the substance of the dermis, and presenting every variety of com- 

 plexity, from the simplest pouch-like follicle to the sacculated and lo- 



* The anatomy of the skin. 1. The epidermis, showing the oblique laminae 

 of which it is composed, and the imbricated disposition of the ridges upon its 

 surface. 2. The rete mucosum or deep layer of the epidermis. 3. Two of the 

 quadrilateral papillary clumps, such as are seen in the palm of the hand or sole 

 of the foot; they are composed of minute conical papillae. 4. The deep layer 

 of the cutis, the corium. 5. Adipose cells. 6. A sudoriparous gland with its 

 spiral duct, such as is seen in the palm of the hand or sole of the foot 7- 

 Another sudoriparous gland with a straighter duct, such as is seen in the scalp. 

 8. Two hairs from the scalp, enclosed in their follicles ; their relative depth in 

 the skin is preserved. 9- A pair of sebaceous glands, opening by short ducts 

 into the follicle of the hair. 



