276 



GENERAL PHYSIOLOGY 



at the moment of the withdrawal of food, but lives for some time 

 at the expense of the materials of its own cell-body. If these be 

 consumed, it gradually perishes, just as a clock that is not wound 

 up gradually runs down and then stops. The phenomena of 

 inanition have been studied most carefully in compound multi- 

 cellular organisms, especially vertebrates, and an important task in 

 this field is left for cell-physiological investigation. 



Since it is a characteristic peculiarity of living substance that it 

 is continually undergoing spontaneous decomposition, it is clear 

 that in fasting animals metabolic equilibrium must be disturbed. 

 In the decomposition-products of living substance, nitrogen, 

 carbon, hydrogen, oxygen, etc., are continually being excreted, 

 while there is no new 



individual cell so in 



income. The result is that, as in the 

 the multicellular organism, the living- 

 substance is gradually consumed and the 

 organism decreases in weight. The 

 animal lives for some time upon its own 

 tissues. It is, therefore, conceivable that 

 as regards their excreta fasting herbivora 

 are like carnivora. The urine of herbiv- 

 ora, which during normal nutrition is 

 alkaline and . turbid, becomes during 

 inanition acid and clear like that of 

 carnivora ; for during inanition herbivora 

 live upon their own, that is, upon animal 

 tissue, and hence in a certain degree 

 become carnivorous. The living sub- 

 stance gradually consumes itself, until 

 the body- weight has undergone so great 

 a loss that the animal dies. By many 

 experiments Chossat ('43) established 

 this limit of decrease of weight, and found 



that with widely different animals death appears when the loss of 

 weight has reached approximately O4 of the whole body-weight. 

 This limit is reached by different animals at very different 

 times. Frogs live longer than a year, and Proteus anguineus, a 

 peculiar amphibian of the Adelsberg grotto, lives several years 

 without food. Man dies in a relatively short time. In earlier 

 times opportunities for investigating human beings who were 

 fasting for a long time were rare, and the early results are to be 

 accepted with caution. Thus, in the year 1831 in Toulouse a 

 convict, who would take only water, is said to have died only after 

 sixty-three days. In later times, with the appearance of the 

 professional faster physiologists have had more frequent opportunity 

 for making exact investigations on fasting men. Luciani ('90) 

 has produced a striking monograph upon fasting, based upon 

 investigations of the well-known Succi, who undertook a thirty 



FIG. 125. Cotpidium colpoda, a 

 ciliate-infusorian cell, a, In the 

 normal condition ; b, in the con- 

 dition of inanition. The cell- 

 body has become smaller and 

 more transparent, and the gran- 

 ules in the interior have disap- 

 peared. Magnification in both 



260. (After observations 

 and drawings by Jensen.) 



