ALIMENTARY TRACT AS AN ABSORPTIVE SYSTEM. 297 



of fatty acids to fat in the faeces is much higher when no bile 

 is present than when it is. Normally, two-thirds to seven- 

 tenths of the fatty substances present in the faeces are fatty 

 acids, while in the absence of bile eight-tenths to nine-tenths 

 are fatty acids, the rest neutral fat. It was formerly believed 

 that this could be explained through MOORE and ROCK- 

 WOOD'S observation that the fatty acids are more soluble in 

 the presence of bile and hence are more readily absorbed 

 when this secretion is present, but MUNK has shown that 

 the reverse is true by finding that fatty acids are more readily 

 absorbed than neutral fats in the absence of bile. 



The many observations at hand on the effect of removal 

 of the pancreas or ligation of its duct all agree that the absorp- 

 tion of fat is much hampered by such procedures. Vastly 

 different figures are, however, found in the literature to 

 illustrate the extent to which the absorption of fats is de- 

 creased. When not in the form of an emulsion fats are 

 absorbed in very slight measure when the pancreatic secretion 

 is entirely lacking. HEDON and VILLE state that 10 percent 

 of an olive-oil feeding may be absorbed and 22 percent of the 

 fat of milk. MINKOWSKI and ABELMANN give even higher 

 figures for the absorption of oil in the form of an emulsion, 

 28 to 53 percent of milk-fat. 1 That any fat at all should be 

 absorbed in the absence of a pancreatic secretion was long 

 regarded as a remarkable fact. This can no longer be con- 

 sidered a mystery since we have become acquainted with 

 the almost universal distribution of lipase in the tissues and 

 fluids of the body. The mucous membrane of the small 

 intestine contains this ferment, and no doubt some is found 

 in the secretions of this viscus. To the ferment present from 

 these sources must be attributed whatever digestion and 

 absorption of fat we may encounter in an animal deprived 

 of its pancreatic secretion. With the limited amount of 

 lipase present under these circumstances it cannot seem 



1 Quoted from MUNK, 1. c., p. 325. 



