PARTS OF ANIMALS 



as being more literal and at the same time less mis- 

 leading than " excrement." " Surplus " would have 

 been even better if the word had been a little more 

 manageable. 



" Residue " is so called because it is that which is 

 left over when the living organism, by acting upon 

 the nutriment which it has taken, has provided itself 

 ^vith a sufficient supply for its upkeep. Some of the 

 surplus will be useless material contained in the food 

 from the outset, or else has been produced during 

 the process of reducing the food into a condition 

 suitable for its purposes in the body. The useless 

 residues include the excrements. In order to appreci- 

 ate the status of the useful residues the outlines of 

 the processes through which the food passes must be 

 kept clearly in mind. Briefly, then, the food is 

 masticated in the mouth, then passed on to the 

 stomach and then the heart, where it is concocted " 

 by means of heat — in other words, it is turned into 

 blood, which is the " ultimate nourishment " ; and 

 this, when distributed into the blood-vessels, suppHes 

 the body with nutrition. Generally, however, more 

 blood is produced than is necessary for the actual 

 upkeep of the body, and this surplus undergoes a 

 further stage of concoction, and is used by Nature 

 in various ways. Marrow is a residue ; so are semen, 

 catamenia, milk. Sometimes, when nutrition is 

 specially abundant, the surplus blood is concocted 

 into fat (lard and suet). And some of the blood, 

 reaching the extremities of the vessels in which it 

 travels, makes its way out in the form of nails, claws, 

 or hair. The Aristotelian doctrine of residues came 

 down to Shakespeare, as is shown by the passage 



*• See page 34. 



33 



