THE COMMON INTEGUMENT 



1063 



the lines on the tips of the fingers and thumbs form distinct patterns unlike those of 

 any other person. A method of determining the identity of a criminal is based on 

 this fact, impressions ("finger-prints") of these lines being made on paper covered 

 with soot, or on white paper after first covering the fingers with ink. The deep 

 surface of the epidermis is accurately moulded upon the papillary layer of the 

 corium, the papillae being covered by a basement membrane; so that when the 

 epidermis is removed by maceration, it presents on its under surface a number of 

 pits or depressions corresponding to the papillae, and ridges corresponding to the 

 intervals between them. Fine tubular prolongations are continued from this 

 layer into the ducts of the sudoriferous and sebaceous glands. 



Duct of 



sudoriferous' 



gland 



Tactile 

 corpuscle' 



Duct of 



sudoriferous. 



gland 



Adipose tissue J 

 Artery 



Pacinian 

 corpuscle ' 



Stratum 

 corneum 



^Stratum 



lucidum 

 'Stratum 



granulosum 

 'Stratum 



mucosum 



Stratum 

 germinativum 



=." Dermis 



Sudoriferous 

 gland 



- Nerve 



Fia. 940. A diagrammatic sectional view of the skin (magnified). 



The epidermis consists of stratified epithelium w r hich is arranged in four layers 

 from within outward as follows: (a) stratum mucosum, (6) stratum granulosum, (c) 

 stratum lucidum, and (d) stratum corneum. 



The stratum mucosum (mucous layer} is composed of several layers of cells; those 

 of the deepest layer are columnar in shape and placed perpendicularly on the 

 surface of the basement membrane, to which they are attached by toothed extrem- 

 ities; this deepest layer is sometimes termed the stratum germinativum; the succeed- 

 ing strata consist of cells of a more rounded or polyhedral form, the contents of 



