DIGESTIVE APPARATUS. 153 



can, therefore, not define the outlines of these organs with 

 any degree of exactness in the living animal. In a general 

 way, however, these outlines may be defined as follows : 



The right portions of the colon and the cecum occupy the 

 right side of the abdominal cavity. We may be aided in de- 

 finmg the position of the various portions of the intestinal 

 tract by drawing a line along the abdominal border of the 

 area of percussion for the lung, and a second line along the 

 course of the last rib and extending over the cartilages of the 

 floatmg ribs; between these two draw a third (horizontal) line 

 at the middle of the body of the animal. This outlines three 

 areas on the right side of the abdomen. The anterior (lower) 

 area is occupied, in the main, by the right upper portion of the 

 colon, which occupies a position just behind the diaphragm 

 The ventral portion of the colon lies opposite the cartilages of 

 the false ribs, in the region of the 8th to the 17th ribs, about 

 half of Its volume being situated above and the other half 

 below the cartilages. 



The cecum occupies the whole of the third or posterior 

 area as well as the upper anterior area as far as the 14th rib 

 The small intestines and the floating colon occupy a position 

 behind the cecum beginning at a vertical line dropped from 

 the external angle of the ilium. 



On the left side (Fig. 32, p. ) (in the horse) the 



small intestine and the floating colon occupv the region of 

 the upper two areas while the third, or lower, area is occupied 

 by the left portion of the colon, extending up to the ilium. The 

 lower portion of the colon occupies the greater area of the 

 abdominal wall, the 'upper portion being placed more toward 

 the median line of the abdomen, but approaching the abdominal • 

 wall as It courses forward, touching it through the medium of 

 the diaphragm between the Tth an.d 11th ribs. 



By careful observation of their topographical relationship, 

 and with the aid of percussion, we can readily determine the 



