160 PERISSODACTYLA. 



the basis of the skull is turned back, so that it stands perpendicular, 

 not horizontal as in man; so what we say 'runs back' in man 'runs 

 up ' in brutes ; and to conceive the situation of this better, it must be 

 understood that the pharynx does not come near the ventricles by four 

 or five inches, which allows for the position of these two bags between 

 them. 



[Loose Note on the same structure from, apparently, another 

 dissection.'] 



The Eustachian tube is, at its beginning, cartilaginous; but opens 

 into a large cavity just on the inside of the pterygoideus internus 

 muscle, large enough to contain half a pint of water; but, from the 

 beginning of the tube to its termination in the bony part, it is a groove 

 running along the basis of the skull. 



The val vula major of the brain * is a strong membrane. 



The heart is not so fasciculated as the human. The valvulae mitrales 

 are not two entire valves, but are joined at their bases, which makes a 

 valvular circle round the mouth of the ventricle, but at the part of 

 union it is not so broad as in the human. The tricuspid valves were 

 almost three distinct valves, but were joined at their bases 2 . 



The lungs are but one lobe on each side, except the lobulus medius ; 

 however, at their anterior or rather inferior edges, where they enclose 

 the pericardium, they are a little divided so as to make a sulcus for the 

 heart. This appears to be equal on each side, so that the heart lies in 

 the middle. 



The abdomen is surrounded by an elastic membrane bike white 

 leather, which is pretty thick, and is on the outside of the muscles. 



The stomach 3 is somewhat similar in situation and shape to the 

 human ; however, it is rather shorter, the small end not running into 

 so slender a part. 



The duodenum passes to the right, then down, and at the last part it 

 is a little convoluted and loose ; it soon crosses the spine behind the 

 root of the mesentery and the union of the ileum, caecum and colon ; 

 then comes forward on the left of the mesentery and becomes a loose 

 intestine. The duodenum, jejunum, and ileum, have no valvuloe conni- 

 ventes. The ileum passes into the caecum, which is 2 feet long and 

 near a foot diameter, ending in a narrow point. The caecum has four 



i [Hunt. Prep. No. 1329.] 



2 [The structure of the arteries is shown in Hunt. Preps. Nos. 938 — 955 ; of the 

 veins in Nos. 964 and 980.] 



3 [Hunt. Preps. Nos. 545—547.] 



