508 Messrs. Ellis and Gardner. Origin and [Aug- 14> 



80° C: The weight of partially dry stuff was 362 grammes. The weights of 

 the animals were taken at the beginning of the experiment and periodically 

 afterwards with the following result : — 





At beginning. 



On third day. 



On last day. 



Cat I 



lbs. ozs. 

 8 2 

 7 2 

 6 2 



5 4 . 



lbs. ozs. 

 7 14 

 6 14 

 6 1 

 5 4 



lbs. ozs. 

 7 12 

 7 2 

 5 5 

 5 6 



„ II 



„ III 



,. IV 





The faeces were extracted in a Soxhlet's apparatus with ether for 19 days 

 and yielded 4*3985 grammes of unsaponifiable matter. This was a dark stiff 

 vaseline-like substance. The unsaponifiable matter was repeatedly crystal- 

 lised from alcohol, but it proved exceedingly difficult to purify. Eventually 

 O'Oo gramme pure coprosterol, melting 99° — 102°, was obtained. The impure 

 crystalline crops and all the mother liquors, after evaporating to dryness, were 

 separately treated in pyridine solution with excess of benzoyl chloride. On 

 pouring into water the crude benzoates which separated were treated in a 

 similar manner to that described in a former paper.* 1*7272 grammes of 

 benzoate was obtained. This melted at 125° — 128° without showing any 

 play of colours. It appeared likely that we were dealing with a mixture of 

 cholesterol - and coprosterol benzoates, and the substance was, therefore, 

 fractionally crystallised from ethyl acetate. The first crop of crystals on 

 heating began to soften at 130° C. and melted to a turbid liquid at 141° C, 

 which became clear at 105° C. On cooling, the play of colours characteristic 

 of cholesterol benzoate was shown in a well-marked manner. A microscopic 

 examination showed that it consisted of the characteristic plates of cholesterol 

 benzoate with a comparatively small quantity of coprosterol benzoate. A 

 later crop, which a microscopic examination showed to consist mainly of 

 coprosterol benzoate with only a very few raystals of cholesterol benzoate, 

 melted at 117° — 119° to a clear liquid. Pure coprosterol benzoate melts at 

 120° — 121° C. Evidently, therefore, a mixture of cholesterol and coprosterol 

 was excreted, the total weight being 1*4004 grammes, corresponding to an 

 output per day per cat of 0*05 gramme. 



Heart muscle contains between 066 and 0*071 per cent, of cholesterol,*!* 

 so that the animals received in their food about 3*5 grammes of cholesterol. 



* " Origin and Destiny of Cholesterol in the Animal Organism," Part IV, ' Eoy. Soc. 

 Proc., : B, vol. 81. p. 129. 



t " Cholesterol Content of Heart Muscle," * Journ. Physiol.,' vol. 38, 1908, ' Proc.,' p. 1 . 



