Origin and Destiny of Cholesterol in the Animal Organism. 505 



REFERENCES. 



Breinl, A. (XI, 1907), "On the Morphology and Life History of Spiroehceta duttoni," 



'Ann. Trop. Med. and Parasitol.,' vol. 1, pp. 435 — 438, 1 pi. 

 ^utton, J. E., and Todd, J. L. (XI, 1907), "A Note on the Morphology of Spirochceta 



duttoni," ' Lancet,' 1907 (ii), pp. 1523—1525. 

 Fantham, H. B. (VI, 1907), "Spirochceta {Trypanosoma) balbianii (Certes), its Mos r eruents, 



Structure, and Affinities ; and on the Occurrence of Spirochosta anodontoe (Keysselitz) 



in the British Mussel, Anodonta •cygnea" 'Ann. Mag. Nat. Hist.,' ser. 7, vol. 19, 



pp. 493 — 501 (prelim, communic). 

 Fantham, H. B. (1, 1908), "Spirochata {Trypanosoma) balbianii (Certes) and Spirochasta 



anodonUe (Keysselitz) : their Movements, Structure, and Affinities," 'Quart. Journ. 



Microsc. Sci.,' vol. 52, pp. 1 — 73, 3 pis. 

 Mackinnon, D. L. (1909), "Observations on the Division of Spirochetes," ' Parasitology,' 



vol. 2, pp. 267—280. 



Nuttall, G. H. F. (VIII, 1908), " Spirochsetosis in Man and Animals " (Harben Lecture II), 



1 Roy. Inst. Publ. Health Journ.,' pp. 449—464. 

 Swellengrebel, N. H. (VII, 1907), " Sur la Cytologic comparee des Spirochetes et des 



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The Origin and Destiny of Cholesterol in the Animal Organism. 

 Part VI. — The Excretion of Cholesterol by the Cat. 



By 6. W. Ellis and J. A. Gakdner, Lecturer in Physiological Chemistry, 



University of London. 



(Communicated by Dr. A. D. Waller, F.E.S. Eeceived August 14, 1909.) 



(From the Physiological Laboratory, South Kensington, University of London.) 



In an earlier paper* of this series the results of a number of estimations 

 of the cholesterol content of the faeces of a dog fed on a variety of diets — 

 animal and vegetable — were described. It was shown that the cholesterol 

 found in the case of meat diets could be entirely accounted for by that 

 present in the food, and from a general survey of the whole of the results, 

 the opinion was expressed that the whole of the cholesterol of the bile is not 

 excreted in the fasces, and must therefore have been either totally destroyed 

 or reabsorbed in the gut along with the bile salts. In the case of a diet of 

 raw brain, it was found that the cholesterol was not excreted as such, but 

 entirely in the form of coprosterol. This was subsequently! found to be the 

 case when cats were fed on either raw or cooked brain. 



* 'Roy. Soc. Proc.,' B, vol. 80, 1908. 

 t 'Roy. Soc. Proc.,' B, vol. 81, 1909. 



