THE FATS OCCURRING IN THEM. 321 



mucin" precipitable by water and acetic acid. I have three times 

 observed a similar body in the fluids of hydrocele. 



Mack found 0'99^ and 0'91^ of extractive matters in the liquor 

 amnii at the full term of pregnancy, Scherer only 0'06- at the same 

 period, but 0'724-J in that of a foetus in the fifth month. 



We find only small quantities of neutral saponifiable and sapo- 

 nified fats in the transudations ; but even here the nature of the 

 capillaries through which these transudations pass is not without 

 some influence, for the fluids of the capillaries of the cerebral 

 membranes, of the pericardium, of the subcutaneous areolar tissue, 

 as well as of the aqueous humor, are very poor in these substances; 

 although here also, in certain pathological cases, they are often 

 increased relatively to the albumen ; but this is only the case 

 when the fluid in question is very deficient in albumen. In 

 transudations which are richer in albumen, the relation between 

 the saponifiable and saponified fats differs little from that exhibited 

 in the blood. We find, however, from a more exact comparison 

 of the individual analyses, that the capillaries must possess a 

 greater permeability for these fats than for the albumen. Thus, 

 for instance, the amount of fat in the solid residue of fibrinous 

 transudations is always somewhat greater than that in the 

 solid residue of the intercellular fluid of the blood ; and this pro- 

 bably contributes in some degree to the plasticity of the transu- 

 dations, to the formation of pus-corpuscles, &c. The liquor amnii 

 forms an exception to the general experience on this point; for in 

 the latter months of pregnancy, when its albumen is diminished, 

 it becomes very rich in fat, and indeed has been found to be actu- 

 ally turbid from the presence of fat-globules : this fat is, however, 

 not a product of secretion of the amnion, but is secreted by the 

 sebaceous glands of the foetus ; in fact it is a portion of the vernix 

 caseosa. Mack* found 0'125 and 0'013 -g- of fat in the liquor amnii, 

 and I found 0'09S at the full period. 



The non-saponifiable fats or lipoids, cholesterin and serolin, 

 usually occur in transudations in far larger quantity than the true 

 fats : cholesterin is especially found in the fluid of ovarian dropsies, 

 and even oftener in the fluid of hydrocele, in such quantity that 

 these transudations present the appearance of opaque fluids in 

 which glistening nacreous bands of crystals may be seen on agi- 

 tation, or even occur as a soft semi-fluid mass of cholesterin. As 

 a general rule, transudations, and especially those of a normal 

 character, are by no means so rich in cholesterin as to admit of 



* Heller's Arch. Bd. 2, S. 218224. 

 VOL. II. Y 



