NUTRITIVE PRINCIPLES OF PLANTS. 957 
the acid again ina state of purity. De Saussure has mentioned an- 
other body, which he found in small quantities in impure gluten ; 
he calls it mucin. It contains nitrogen; its composition cannot 
be very different from vegetable fibrin, as the unpurified gluten 
of wheat is very little different in composition from vegetable 
fibrin and albumen. 
The analyses of the constituents of Animals show, in a very 
distinct manner, how entirely the azotized principles of Vegeta- 
bles agree in composition with them. 
The following are Mulder’s analyses after abstracting the in- 
combustible parts :— 
Fibrin. Albumen. Casein. 
From Eggs. From Serum. 
Carbon ... 54°56 54°48 54°84 54°96 
Nitrogen aL 72 15°70 15°83 15°80 
Hydrogen. . 6°90 701 7:09 715 
Oxygen 
Phosphorus i 22°82 22°81 22°24 22°09 
Sulphur... 
These results agree perfectly with those of Dr. Scherer, who 
obtained— 
Fibrin, Albumen. 
In the whey of 
From Eggs. From Serum. sour coagulated Milk. 
Carbon ... 54°454 55000 55:097 54°507 
Nitrogen . 15°762 15°920 15948 15°670 
Hydrogen 7'069 7:073 6°880 6°900 
Oxygen . 
Phosphor 29-715 + 22007 93-075 22-923 
Sulphur... 
Dr. Scherer’s analyses, according to the qualitative method, 
gave the proportion of 1 of nitrogen to 6°9, 7°1, 7:2, 7°3 of car- 
bon. When chromate of lead was used, the result in the last 
tube of gas was 1:8. ‘This last result was obtained also by 
Drs. Will and Varrentrapp’s new method. When milk is al- 
lowed to stand till it becomes sour, what remains in the whey, 
and the analysis of which is here given, is clearly albumen, and 
is precipitated by boiling: it is certainly albumen, as caseum is 
more soluble in hot than in cold liquids. 
A single glance at the results of these analyses, shows that 
graminivorous animals receive, in the vegetables which they eat, 
the ingredients of their blood, namely, their albumen and fibrin, 
