94 IV. 2. 



it is altogether wanting, as is the case in a certain district of 

 Chalcis in Euboea.^ Another fact, which shows that the opinion 

 of these writers is erroneous, is that the gall-bladder in fishes 

 is separated, as already mentioned, by a considerable interval 

 from the liver. No less mistaken seems to be the opinion of 

 Anaxagoras and his followers, that the gall-bladder is the cause 

 of acute diseases, inasmuch as it becomes over-full, and spirts 

 out its excess into the lung, the blood-vessels, and the thest 

 For, almost invariably, those who suffer froni these acute forms 

 of disease are persons who have no gall-bladder at all, and, 

 were they to be dissected, this fact would be quite evident.^^ 

 Moreover there is no kind of correspondence between the 

 amount of bile which is ' present in these diseases and the 

 amount which is exuded.'^ The most probable opinion is that, 

 as 'the bile when it exists in any other part of the body is a 

 mere residuum or a product of decay, so also when it exists in 

 the region of the liver it is equally excremental and has no 

 further use ; jtist as is the case with 'the dejections of the 

 stomach and intestines. For though even the residua are occa- 

 sionally used ^^ by nature for some useful purpose, ye^- we must 

 not in all cases expect to find such a final cause ; for granted 

 the existence in the body of this oi« that constituent, with such 

 and such properties, many results must ensue merely as necessary 

 consequences of these properties.^^ All animals, then, whose liver 

 is healthy in composition and supplied with none but sweet 

 blood, are either entirely without a gall-bladder, or have merely ^* 

 bile-containing ducts ; or are some with and some without such 

 parts. Thus it is that the liver in animals that have no gall- 

 bladder is, as a rule, of good colour and sweet ; and that, when 

 there is a gall-bladder, that part of the liver is sweetest, which 

 lies immediately underneath it. But, when animals are formed 

 of blood less pure in composition, the bile serves for the excretion 

 of its impure residue. For the very meaning of residuum is that 

 it is the opposite of nutriment, and of bitter that it is the opposite 

 of sweet ; and sweet blood it is which alone is nutritious,^^ So 

 that it is evident that the bile, which is bitter, cannot have any 

 useful end, but must simply be a purifying excretion.^^ It was 

 therefore no bad saying of old writers that the aUsence of a 

 gall-bladder gave long life. In so saying they had in mind 

 deer and animals with uncloven hoofs. For such have no 

 677a. 



