432 NUTRITION. 



first third the loss was 0*393, during the second third it was nearly 

 0'260, and during the last third 0*347. 



The entire loss of weight which the starving animal undergoes 

 previously to its death varies very considerably with the species ; 

 thus Chossat found that rabbits (taking the mean of five experi- 

 ments) died when they had Iost37'4 of their weight; guinea-pigs 

 (five experiments) when they had lost 33'0 J ; turtle-doves (fifteen 

 experiments) when they had lost 37'9; domestic pigeons (twenty 

 experiments) when they had lost 41*6$ ; hens (two experiments) 

 when they had lost 52*7$ ; and crows (one experiment only being 

 made) when they had lost 31*1 %. As an average of all the forty- 

 eight experiments 39*7$ seems to be about the loss of weight which 

 the body undergoes previously to death by starvation. Hence in 

 the higher animals the organism loses from l-3rd to 2-5 ths of its 

 weight before it succumbs to starvation. 



Taking the averages in Chossat's experiments, it was found 

 that the mammals, during the process of starvation, lost daily 4'0^ 

 of their weight, and the birds 4'4--, the mean of all the observations 

 on both classes being 4*2 . We find, therefore, that the animal body 

 loses daily about l-24th of its mass by the metamorphosis of its 

 tissues ; a result which is in the most complete accordance with 

 the result which had been already obtained by a different method 

 (see p. 425), namely, that the daily quantity of properly selected 

 food which an animal requires must amount to at least l-23rd of 

 its bodily weight. 



Chossat has ascertained and compared in pigeons the relative 

 losses of weight which each individual organ undergoes in cases of 

 starvation an investigation of the highest importance in relation 

 to general physiology. We must here confine ourselves to the mere 

 enumeration of the following results : the greatest amount of loss 

 was experienced by the fat, 93*3^ of this substance disappearing 

 during the process of starvation ; the blood suffered next in propor- 

 tion, its loss amounting to 75'Og-; of the muscles there disappeared 

 42*3$ ; of the bones only 16'78-j and of the nerves the least of all, 

 namely l*9f. If we compare, as Chossat has done, the total loss 

 of bodily weight with the absolute amount of loss of the individual 

 organs or tissues, it follows that the daily diminution of bodily weight 

 may be thus sub-divided : half may be referred to the muscular tis- 

 sue, a quarter to the fat, and the remaining quarter to all the other 

 organs. Hence it is chiefly the products of decomposition of the 

 muscular tissue and of the fat which are represented in the 

 excretions. 



