OF THE SKIN IN GENERAL. 207 



thickness of the skin together. The sub-cutaneous cellular 

 tissue is traversed by large veins, by numerous arteries, lym- 

 phatics and nerves. 



294. The cutaneous or sebaceous follicles* bear the strong- 

 est resemblance to the mucous follicles. 



They exist throughout the whole extent of the skin, at least 

 it is so admitted, the palm of the hand and sole of the foot 

 excepted. Their existence is conceded, because the whole 

 surface of the skin is covered with the sebaceous humour;* 

 because by careful dissection, aided by a lens, they are dis- 

 covered in places where they are excessively slender; and 

 because certain morbid changes render them evident in places 

 where they are not otherwise perceptible. They are particu- 

 larly abundant where there are hairs, in the vicinity of orifices 

 and in the folds of the groin and axilla. They are placed in 

 the thickness of the skin or beneath it; an excellent view of 

 them may be attained by cutting through the skin obliquely. 

 Their orifices form tolerably distinct pores on the surface. 

 They are about the size of a grain of millet, or even smaller; 

 they vary in size; those of the nose are tolerably large, in the 

 cheeks they are much smaller. Their figure is that of a little 

 ampulla. They are generally simple and separate; those of 

 the nose, however, are very closely approximated; some of 

 them are confluent, or compound. They consist in a little 

 ampulla formed by the skin, thinned, reflected, and furnished 

 with numerous vascular ramusculi. They contain an oleo-al- 

 buminous matter that differs a little in the various regions of 

 the body. 



295. The anatomical texture and composition of the skin, 

 are delicate points of anatomy, that have greatly exercised the 

 patience of observers, and upon which they are far from agree- 

 ing. From a very early period, it was seen, that the skin 

 was composed of two layers, one thick and deep, the other 

 thin and superficial. Malpighi perceiving, that in a bullock's 

 tongue, the papilla of the derm is are separated from the epi- 



* J. Ch. Th. Reusse, prseside Autenrieth, de Glandulis sebacefs dissert, etc, 

 Tubingoe, 1807. 



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