96 General Aspects of Fasting [Sept. 



tion crosses that representing the Creatinine Output. This phenome- 

 non has been termed by us the "creatine crossing" and is believed 

 to be very significant. It occurs with great uniformity a few days 

 previous to the decrease in the total nitrogen excretion that precedes 

 the pre-mortal rise of excreted nitrogen. By means of the " creatine 

 crossing" the length of the subsequent Hfe tenure of the animal 

 may be quite closely estimated. 



Certain pathological constituents, other than creatine, may ap- 

 pear in the urine as the result of fasting, such as acetone, diacetic 

 acid, lactic acid, bile pigments, albumin, etc. 



The processes in the large intestine during fasting have received 

 but httle attention. Various authorities contend that it is difficult 

 to make a Separation (2, 18) of fasting feces. Müller (19a) has 

 shown that indican, which is now considered as an index of intes- 

 tinal putrefaction, disappeared upon the third day of fasting. We 

 have been able to make an undoubted Separation of fasting feces 

 and have found indican present during the whole of a seven day 

 fast on man {22,), Fasting feces are distinct from those of the 

 normal individual in that they are of a peculiar brown color and are 

 pasty in consistency. The percentage of nitrogen present is higher 

 than in normal feces. The bacterial content of feces has received 

 but little attention and only recently have results upon the bacterial 

 content of fasting feces been determined. The results indicate a 

 lovver percentage content of bacteria (3). 



There is not an equal wasting of all of the organs and tissues 

 of the body, those organs most necessary for the maintenance of 

 life show only a slight decrease in size and weight, while others are 

 reduced to but a fraction of their original proportions. Thus the 

 heart, lungs, and nervous System exhibit but little change while the 

 muscles and fatty tissues exhibit a marked reduction of both volume 

 and weight. The organs of regeneration are also resistant to the 

 ravages of a fast. This fact is of especial significance for it demon- 

 strates the tendency of nature to preserve the species. 



A histological examination of the tissues and organs of fasting 

 animals shows a decrease in the volume of the cells as a whole and 

 of the nuclei. MorguHs (19) has shown that the decrease in the 

 volume of the cells of the Salamander is greater than that of the 



