00 . SECRETION. 



The microscopical examination of the vernix caseosa is 

 interesting from an anatomical point of view, and possesses 

 considerable importance in certain medico-legal questions. 

 The cells are polyhedric in form, somewhat flattened from 

 mutual compression, and have a diameter of from 12 1 00 to 

 -5^5- of an inch. Their angles are irregular and rounded, 

 not possessing that sharpness of definition which charac- 

 terizes the epidermic cells of the foetus. They are colorless, 

 transparent, very often folded upon themselves, and have no 

 nuclei. The cells themselves are very slightly granular, but 

 a few dark fatty granules sometimes adhere to their exterior. 

 These cells have no analogy with the ordinary epidermic 

 cells, but resemble rather the cells found in sebaceous collec- 

 tions. They are regarded, therefore, by Robin, as derived 

 entirely from the sebaceous glands. 1 The secretion of these 

 glands is discharged upon the surface, and disappears in 

 great part, leaving a residue of altered epithelial cells. 

 It is on account of the absence, to a great degree, of oily 

 matter, that the vernix caseosa is not softened by gentle 

 heat. 



The function of the vernix caseosa is undoubtedly pro- 

 tective. If we attempt to make a microscopical preparation 

 of the cells with water, it becomes evident that the coating 

 is penetrated by the liquid with very great difficulty, even 

 when mixed with it as thoroughly as possible. Indeed, 

 we never observe at birth the peculiar effects of prolonged 

 contact of the cutaneous surface with water. The protect- 

 ing coating of vernix caseosa allows the skin to perform its 

 functions in utero, and at birth, when this coating is removed, 

 the surface is found in a condition perfectly adapted to ex- 

 tra uterine existence. It is not probable that the vernix 



1 ROBIN ET TARDIEU, Memoire sur Vexamin microscopique des laches formees 

 par le meconium et Fenduitfcetal, pour servir d Thistoire medico-legale de V infan- 

 ticide ; extraitdes Annales d> hygiene publique et de medecine legale, Paris, 1857, 2e 

 serie, tome vii. 



