SEROLIN. 279 



are often found in the liver, and degenerated ovaries and testicles, 

 often contain a large amount of cholesterin. 



I once found the choroid Plexus in the brain perfectly en- 

 crusted with cholesterin. 



In encysted tumours, (especially in meliceris) as well as in car- 

 cinomatous and other tumours, we often meet with cholesterin. 



In the solid excrements we may generally recognise traces of 

 cholesterin; and in the meconium this substance is present in 

 very considerable quantity. 



In pulmonary expectoration I have only found cholesterin in 

 the cheesy concretions ejected in advanced phthisis, and when 

 vomicae are already present. 



In the urine, as far as I know, no cholesterin has yet been 

 found. 



[Moller states that he has twice discovered cholesterin in the 

 pellicle which forms on the urine during pregnancy, but I know 

 nothing of his character as an observer. See Casper's Wochenschr. 

 1845, N. 2, 3 ; or my translation of Simon's Animal Chemistry, 

 vol. 2, p. 333. G. E. D.] 



Origin. In regard to the origin of cholesterin, which is 

 never found in the vegetable kingdom but only in the animal body, 

 we cannot offer even a probable conjecture. Judging from the 

 mode of its occurrence, we must regard it as a product of decom- 

 position ; but from what substances and by what processes it is 

 formed, it is impossible even to guess. Notwithstanding the 

 similarity which many of its physical properties present to those of 

 the fats, we can hardly suppose that it takes its origin from them, 

 since the fats, for the most part, become oxidised in the animal 

 body, whereas in order to form cholesterin, they must undergo 

 a process of de-oxidation. 



SEROLIN. 



This body, which as yet has been very little studied, was dis- 

 covered by Boudet,* in the solid residue of the serum of the blood. 



At an ordinary temperature it appears in nacreous, glistening 

 flocculi, which are very slightly soluble in cold, but dissolve pretty 

 freely in hot alcohol, and in ether, and do not form an emulsion 

 with water. This body has no reaction on vegetable colours, melts 

 at +36, and apparently may be distilled with only partial change. 

 * Ann. de Chim. et de Phys. T. 52, p. 337. 



