1160 



THE ORGANS OF SPECIAL SENSE 



maintains a due thickness, while, at the same time, the growth of the nail in the 

 proper direction is secured. As these cells in their turn become displaced by 

 the growth of new ones- they assume a flattened form and finally become closely 



MATRIX OF NAIL 



RIDGES OF 

 MATR'X 



SULCUS OF 

 MATRIX 



CONCEALED MARGIN 



FIG. 874. The finger-nail com- 

 pletely isolated, seen from the con- 

 vex side. (Toldt.) 



NAIL WALL 



SULCUS OF 

 MATRIX 



FIG. 875. The matrix of the 

 nail or nail bed, with the nail fold 

 and nail walls displayed by the 

 removal of the epidermic portion 

 of the nail or nail proper and the 

 surrounding epidermis. (Toldt.) 



FIBROUS 

 SUBSTANCE 



FIG. 876. Matrix of the 

 nail with partly opened mar- 

 ginal groove of the nail bed, 

 (Toldt.) 



MEDULLARY 

 SUBSTANCE 



FUNDUS OF 

 HAIR FOLLICLE 



SEBACEOUS 

 GLAND 



AHRECTOR 

 PILI MUSCLE 



NECK OF 

 HAIR FOLLICLE 



INNER 

 ROOT SHEATH 



OUTER 

 ROOT SHEATH 



OUTER 

 FIBROUS LAYER 



INNER 

 FIBROUS LAYER 



HYALINE 

 LAYER 



mm 



HAIR BULBv, 



' HA'R PAPILLA 



Fir, 877. A hair of the head still in the course of growth, with hair bulb in longitudinal section (Toldt.) 



compacted together into a firm dense, horny texture. In chemical composition the 

 nails resemble the upper layers of the epidermis, containing, however, a some- 

 what larger proportion of carbon and sulphur (Mulder). 



