( 373 ) 



7^'- till April the 19'V April tlio 2(^1" 2pf and 22"^^ 50 gram com- 

 mercial gelatin, well washed in water, was taken everj' time in two 

 portions, each of 25 gr., just as the casein instead of 50 gr. carbo- 

 hydrate. On Ai)ril 23'f' and 24*'' the lirst diet was again taken. 



In 10 days in which the food daily taken contained 47 gr. i)roteid 

 (the first two days April the 7'^' and the 8''', which were still under 

 the influence of the food taken the preceding days, the urine was 

 not examined) the secretion of creatinin amounted to: 

 V. H. on the average 1.813 gr. (max. J. 921 miji. 1.706 gr.) daily 

 V. „ „ „ 1.850 „ ( „ 1.990 „ 1.723 „) „' 



On the days on which casein or gelatin was taken the secretion 

 of nitrogen increased but the secretion of creatinin not or scarcely'. 

 It amounted on the three casein-days to : 

 V. H. on an average 1.913 gr. (max. 2.009, min. 1.836 gr.) daily 



V. „ „ „ 1.897 „ ( „ 1.934, „ 1.834 „) „ 

 and on the three gelatin-days: 



V. H. on an average 1.800 gr. (max. 1.813, min. 1.783 gr.) daily 

 V. „ „ „ 1.872 \, ( „ 1.811, „ 1.868 „) „ 



Just as in the series of experiments III as was mentioned above, 

 where, after the daily addition of 5 eggs to food which contained 

 47 gr. proteid, only a too insignificant increase of the secretion of 

 creatinin was found to attach any value to it, it appeared now that 

 the addition of casein and gelatin had no important influence whatever, 

 although the added proteid was daily resorbed and desintegrated in 

 the body, as the determination of nitrogen taught. 



A short time ago Folin has communicated ample researches about 

 the constituents of linman nrine and has come to conclusions ^) with 

 which the observations of van Hoogenhuyze and Verploegh are quite 

 in accordance. 



In 1868 Meissner has drawn the conclusion from his obsei*» 

 rations that the origin of creatinin in the organism of mammals 

 must be quite different from that of the urea with which most of 

 the nitrogen is excreted from the body *). Folin draws this conclu-' 

 sion anew and) in connection with his observations about the secretion 

 of other nitrogen containing substances and sulphur-compounds, starts 

 from this point in proposing a new theory about the desintegration of* 

 proteid in the animal body, which he puts in the place of the wellknown 

 theories of VoiT and of Pflüger. In considering the desintegration 

 of proteids in the body, there has been, argues Folin, generally laid 



"i^Amer. Journ. of Physiol. Vol. XIII, p 45. p. 66 p. 117. 

 . 3) 1. c. S. 295. 



