ERRORS ATTRIBUTED TO ARISTOTLE. 195 



fact, it will appear from the following excerpts that Aris- 

 totle gives an account of the structure of the lungs which 

 is almost as good as that of the heart, and that it contains 

 nothing about any prolongation of the windpipe to the 

 heart. 



" "Within the neck lie what is called the oesophagus (so named 

 on account of its length and its narrowness) and the windpipe 

 (apTTjpia). The position of the windpipe in all animals that have 

 one, is in front of the oesophagus. All animals which possess a lung 

 have a windpipe. The windpipe is of a cartilaginous nature and is 

 exsanguine, but is surrounded by many little veins. . . . 



" It goes downwards towards the middle of the lung, and then 

 divides for each of the halves of the lung. In all animals that pos- 

 sess one, the lung is divided into two parts ; but, in those which 

 bring forth their young alive, the separation is not equally well 

 marked, least of all in man. 



" In oviparous animals, such as birds, and in quadrupeds which 

 are oviparous, the one half of the lung is widely separated from the 

 other ; so that it appears as if they had two lungs. And from being 

 single, the windpipe becomes (divided into) two, which extend to 

 each half of the lung. It ia fastened to the great vein, and to what 

 is called the aorta. "When the windpipe is blown up, the air passes 

 into the hollow parts of the lung. In these, are cartilaginous tubes 

 (6ia,(t>vats) which unite at an angle ; from the tubes passages (rp^ara) 

 traverse the whole of the lung ; they are continually given off, the 

 smaller from the larger." (Book i. 16.) 



That Aristotle should speak of the lung as a single 

 organ divided into two halves, and should say that the 

 division is least marked in man, is puzzling at first ; but 

 the statement becomes intelligible, if we reflect upon the 

 close union of the bronchi, the pulmonary vessels and the 

 mediastinal walls of the pleurae, in mammals ; * and it is 



* In modern works on Veterinary Anatomy the lungs are sometimes 

 described as two lobes of a single organ. 



