378 EXTERNAL INTEGUMENT. 



which have died after being coated with a varnish, he found 

 peculiar crystals of ammonio-mngnesia phosphate in the cellu- 

 lar tissue, the peritoneum, and the muscles. Study of ex- 

 periments of this kind seems to show that when the cutaneous 

 excretion is suppressed, the eliminated products have a ten- 

 dency to pass through the kidney ; this organ is consequently 

 in a state of hyperaemia ; later, an exudation takes place in 

 the uriniferous canaliculi, which are finally obliterated ; this 

 produces retention of the urea with all the consequences 

 which belong to it. We therefore naturally suppose that this 

 substance being retained in the blood, when decomposed, 

 produces ammonia; this, combining with the phosphates, 

 gives rise to the formation of the above-mentioned crystals of 

 ammonia-magnesia phosphate. Researches made as to cause 

 of death in consequence of burns of a large extent of surface 

 yield the same results. The cause of death, following the 

 suppression of cutaneous perspiration, is therefore hyperaemia 

 of the kidneys, followed by parenchymatous exudation in the 

 canaliculi of the kidney, which are at length obliterated, thus 

 causing retention of the excrementitial substances of the 

 urine. 1 



2. Glands and sebaceous Secretions. The sebaceous 

 glands are found in almost every part of the integuments : 

 they are generally joined to the hair (see Fig. 93), as we 

 have already said, but in parts where there is no hair, they 

 are sometimes found alone, as on the glans and the inner 

 surface of the prepuce; finally, certain portions of the in- 

 tegument, such as the palm of the hand, have neither hair 

 nor sebaceous glands (having only sudoriferous glands). The 

 sebaceous glands form, round the hair, numerous culs-de-sac, 

 which may be looked upon as off-shoots of the pilous follicle 

 (Fig. 93 and 95), and surround the neck of the hair some- 

 times in such numbers as to completely hide the pilous appa- 

 ratus. These glands form the most simple type of clustered 

 or racemose glands: their contents consist of epidermal 

 globules, the outer ones being well-shaped and exactly simi- 

 lar to the elements of the layer of Malpighi ; as these globules, 

 however, approach the centre of the glandular cavity, they 

 become infiltered with fat, hypertrophied, and, finally, separ- 

 ate and allow their contents to escape to form a sort of emul- 

 sion of fat and albuminous substances, which fills the cavity of 

 the gland, and is thrown off; the secretion of the sebaceous 



1 See " Gaz. Medic, de Strasbourg." Fcvrier, 1873. 



