INTERMEDIATE METAMORPHOSIS OF MATTER. 447 



of respired carbon considerably exceeds the quantity passing 

 through the bile. When the mineral constituents of the food are 

 much increased, the biliary secretion is relatively more increased 

 than the respiration ; but during starvation the former is more 

 diminished than the latter. Of every 100 grammes of nitrogen 

 which are separated by the kidneys, at most not more than 3 

 grammes pass through the bile (as taurine and glycine), while of 

 100 parts of sulphur from 54 to 86 parts take that course ; under 

 no conditions, however, does the whole of the sulphur pass through 

 the stage of bile. In herbivorous animals scarcely 2-3rds of the 

 glycine separated with the urine in the hippuric acid are contained 

 in the glyco-cholic acid. During starvation we may put down the 

 average typical relation as follows : for every 100 parts of expired 

 carbon there are given off 15 '4 parts of carbon, under the form of 

 urea, by the kidneys. While in fasting animals (the calculations 

 being made for equal bodily weight) the same daily quantities of 

 carbonic acid and urea were secreted, the biliary secretion sunk to 

 such an extent that on the tenth day of inanition only 2-5 ths of the 

 quantity of bile were obtained, which was secreted on the third 

 day. 



There are other interesting points of view which present them- 

 selves when we contrast, in relation to quantity, the elements of the 

 intermediate metamorphoses of matter and those of the final excre- 

 tions with the corresponding elements of the organism or of the 

 blood ; as for instance, when we compare the quantities of the 

 carbon separated by the bile or by the saliva, with that which is 

 separated by the kidneys or lungs, and reduce the numbers of both 

 to 100 parts of the carbon contained in the organism or in the 

 blood. As a standard of comparison Bidder and Schmidt employed 

 results which they had obtained from a cat, and which, as they 

 stand at present isolated to science, we must on no account omit. 

 They found that each kilogramme's weight of the animal (which was 

 a young cat weighing 1505 grammes) contained 



Muscles and tendons .... 450-36 grammes, or when dry 107' 64 grammes. 



Bones 147*45 80'36 



Skin 120-86 57'05 



Intestinal tract 64-91 14'60 



Brain and spinal cord .... 19'40 4 29 



Liver 47'5l 1278 



Lungs .... 10-78 2'24 



Kidneys 9'00 1 85 



Spleen 3'16 0'67 



