THE EESPIEATORY APPARATUS. 307 



last rib but one^ so tbat the last intercostal space is not lined 

 by pleura. The rumen^ therefore, giving its various sounds, 

 occupies a large part of the posterior division of the left 

 side, while the liver lies on the right, and gives an area 

 of dulness. *^'We must determine the natural sound 

 when the animal ruminates, which may be heard at the 

 lower part of the chest at the level of the xiphoid carti- 

 lage of the sternum. It resembles the gurgling sound 

 when fluid passes from a bottle, and doubtless is due to 

 the liquids in the reticulum; since cattle, when sick, do 

 not generally ruminate, this noise will not be confounded 

 with abnormal sounds. Nevertheless, we have thought 

 right to note it here. We must also distinguish a crepi- 

 tation with a frothy sounds which originates in the rumen 

 when its muscular walls contract; it is audible at the 

 postero-superior part of the left side of the chest^^ 

 (Delafond). Since the shoulder occupies the anterior 

 part of the lateral surface of the chest as far back as the 

 fourth rib, and the diaphragm bulges posteriorly, the area 

 over which auscultation can be profitably performed in the 

 ox is very limited. However, the shoulder may be drawn 

 forwards to a certain extent, so that even the first rib may 

 be felt from behind, and considerable care will enable us 

 to distinguish lung sounds in the posterior region. 



The lateral surface of the chest is divided into superior, 

 middle, and inferior thirds. '' Right side. — In the superior 

 region the vesicular sound is well marked from behind the 

 shoulder to the level of the tenth rib, from which it gradually 

 decreases in intensity to be lost opposite the eleventh. In 

 the median region a loud and sometimes rather rude re- 

 spiratory murmur is heard over the fourth and three fol- 

 lowing ribs, which, however, gradually decreases from the 

 seventh, and is lost over the tenth or eleventh. In the 

 lower region the sound may be said to be bronchial over 

 the fourth and fifth ribs, evidently on account of the con- 

 siderable tube passing to the fourth lobe of the right lung. 

 From the sixth to the ninth rib it is vesicular, and its force 

 decreases from before backwards. Left side. — The superior 

 region simply repeats that of the right side. In the median 



