1911.] Destiny of Cholesterol in the Animal Organism. 469 



living on their own tissues, we find, as was expected, a similar storing up of 

 the cholesterol in the liver. This is very marked in the case of the fat 

 rabbit in Experiment IX, which probably used up the fat directly, and less 

 marked in the case of the lean rabbit in Experiment X, which made 

 a greater demand on its tissues. This result, we think, was also to be 

 expected. In Experiment XI the percentage total cholesterol content of the 

 liver of newly-born rabbits is of the same order of magnitude as that of 

 adult rabbits. What factors govern the relative proportions of free 

 cholesterol and cholesterol esters the experiments do not indicate. 



These results we submit afford striking evidence in support of the 

 hypothesis advanced at the beginning of this paper. 



Addendum on the Examination of the VnsaponifiaMe Matter in the Fceces of 

 Bahbits fed on Ether-extracted Bran. 

 In former investigations on the subject we never succeeded in crystallising 

 cholesterol from the faeces of rabbits fed on extracted bran, but, as in 

 Experiment VIII we succeeded in isolating cholesterol by the digitonin 

 method from the faeces of rabbit G, which had a diet of extracted bran, but 

 into the peritoneal cavity of which olive oil had been injected, it became 

 necessary to examine more clearly the faeces of a normal animal fed in the 

 same way. For this purpose a rabbit was fed for 15 days on extracted bran 

 and the faeces collected. They weighed, after drying, 295 grm., and yielded, 

 after treatment in the manner described, 0*6445 grm. of unsaponifiable oily 

 matter, soluble in alcohol. This residue was dissolved in alcohol and mixed 

 with as much of an alcoholic solution of digitonin as would have completely 

 precipitated the residue had it consisted of pure cholesterol. This was 

 allowed to evaporate to dryness spontaneously, and was obtained free from 

 unchanged oil by means of ether. This oil weighed CK3076 grm., and did 

 not give any sterol colour reaction in chloroform solution with acetic 

 anhydride and sulphuric acicl. The digitonin precipitate, after washing 

 repeatedly with hot water, weighed T2175 grm., but it was not free from 

 digitonin, and was yellowish in colour. It was then finely powdered and 

 washed with about 200 c.c. of ether until colourless. The ether dissolved 

 about 0'25 grm. of solid matter. This solid was insoluble in petroleum 

 ether, but soluble in benzene, and on testing with acetic anhydride and 

 sulphuric acid only gave the sterol colours in a slightrand indefinite manner. 

 The 0"99 grm. of digitonin compound was then heated in xylene vapour until 

 completely decomposed, and the clear xylene solution on evaporation gave 

 a yellow, oily solid. This was only partly soluble in ether, leaving a white, 

 insoluble powder, which did not give any sterol reaction. The ethereal 



2 M 2 



