210 GENERAL ANATOMY. 



evidently consist of a very soft, very cellular projection of the 

 clermis, penetrated by numerous nervous threads, deprived of 

 the neurilema, and of vascular ramusculi, and having an erec- 

 tile disposition which will be described hereafter (chap. iv). 

 In those places where the papillae are less distinct, although 

 the texture and composition of the dermis are essentially the 

 same, there are fewer nerves ; the vessels, which are very 

 abundant, form a net-work. The blood penetrates constantly, 

 but in variable quantities into the vessels of the dermis. In 

 echymosis of the skin it goes still further, and passes into the 

 mucous body. Fine and penetrating injections, after filling 

 the papillary and vascular body of the skin, sometimes spread 

 beyond it* 



299. The texture of the dermis is that of an areolar web 

 more or less close: the fibre that forms it is peculiar to it. It 

 was considered by the older anatomists as intermediate to the 

 muscular fibre, and the aponeurotic tissue. Some have stated 

 it to be altogether cellular, others ligamentous. Even quite 

 recently, M. Osiandert has maintained that it is distinctly mus- 

 cular on the internal face of the skin. His observations were 

 made on the skin of the abdomen in women who died in par- 

 turition. The tissues to which it bears the greatest resem- 

 blance by the ensemble of its characters, are, the cellular and 

 fibrous tissues. 



300. The dermis is white: its external surface is more or 

 less reddish, according to the greater or less quantity of blood, 

 remaining in its small vessels. Its thickness is not every 

 where the same, varying from one line and a half, to a fourth 

 of a line. In the trunk it is generally greater behind than be- 

 fore ; in the limbs more so externally, than internally. The 

 dermis is particularly very thin in the eye-lids, mammae, and 

 the organs of copulation; very thick, on the contrary, in the 

 palm of the hands, and above all, in the sole of the foot. It has 

 a semi-transparency which renders the colour of the sub-cu- 

 taneous veins visible through the skin. It has a power of re- 



* See Frochaska, disquisitio anat, phyn. or%anismi &c. Vienna:, 1812. 4, 

 f Commentationcs gottingcnses recentiores. Vol. iv. 1820. 



