ii. 4— ii. 5- 3i 



passionate. For their blood is exceedingly rich in fibres;^ and 

 the bull's at any rate coagulates more rapidly than that of any 

 other animal.^ If these fibres, that is to say if the earthy con- 

 stituents of which we are speaking, are taken out of the blood, 

 the fluid that remains behind will no longer coagulate ; just as 

 the watery residue of mud will not coagulate after removal of 

 the earth. But if the fibres are left the fluid coagulates, as also 

 does mud, under the influence of cold. For when the heat is 

 expelled by the cold, the fluid, as has been already stated, passes 

 off with it by evaporation, and the residue is dried up and 

 solidified, not by heat but by cold.'" So long however as the 

 blood is in the body, it is kept fluid by animal heat. 



The character of the blood affects both the temperament and 

 the sensory faculties of animals in many ways. This is indeed 

 what might reasonably be expected, seeing that the blood is 

 the material of which the whole body is made. For nutriment 

 supplies the material, and the blood is the ultimate nutriment. 

 It makes then a considerable difference whether the blood be 

 hot or cold, thin or thick, turbid or clear. 



The watery part of the blood is serum ; and it is watery, 

 either owing to its not being yet concocted, or owing to its 

 having become corrupted ; so that one part of the serum is the 

 resultant of a necessary process, while another part is material 

 intended to serve for the formation of the blood.^^ 



(Ch. ^.) The differences between lard and suet correspond to 

 differences of blood.^ For both are concocted blood ; being that 

 surplus of it, which, though well concocted and highly nutritious, 

 has not been expended in forming the fleshy substance of the 

 animal, but remains over owing to the superabundance of food. 

 That such is the composition of these substances is evident from 

 their sheeny appearance. For a sheeny look in fluids comes from 

 their being compounded of air and of fire.^ It follows from what 

 has been said that no ex-sanguineous animals have either lard 

 or suet ; for they have no blood.* Among sanguineous animals 

 those whose blood is dense are likely to have suet rather than 

 lard. For suet is of an earthy nature, that is to say, it contains 

 but a small proportion of water and is chiefly composed of earth ; 

 and this it is that makes it coagulate, just as the fibrous matter 

 of blood coagulates, or broth? which contain such fibrous matter.* 

 Thus it is that in those horned animals that have no front teeth 

 651a. 



