THE RABBIT. 291 



passing from the thorax dorsal to (beneath in the present 

 position) the pectoral muscles, outwards to the arm. 



137. The linea alba, a faint band of fibrous tissue, more 

 opaque than the general muscular walls of the body, passing 

 from the posterior extremity of the sternum to the symphysis 

 pubis. 



138. The rectus abdominis, a band-like area of 

 muscle lying on either side of the linea alba : its fibres run 

 longitudinally. 



139. The external oblique muscle, just external to the 

 rectus : its fibres run from above downwards and backwards. 



140. The internal oblique, seen by dissecting away part of the 

 external oblique, which it immediately underlies ; its fibres run down- 

 wards and forwards, crossing those of the external oblique. 



141. The transversalis, seen by dissecting away a portion of both 

 external and internal oblique : it lies between the latter and the perito- 

 neum (§ 145), its fibres running nearly parallel to those of the external 

 oblique, 



142. Poupart's ligament, a fibrous cord passing on 

 each side from the symphysis pubis upwards and forwards 

 to the anterior part of the ilium (§ 91). 



143. The blood-vessels and nerves of the legs, 

 passing from the abdominal cavity, beneath Poupart's liga- 

 ment, outwards to the leg. 



144. The abdominal viscera are seen, especially in 

 young subjects, through the thin abdominal walls. 



XIII. Make an incision down the linea alba, from the 

 xiphoid process to the symphysis pubis : from the 

 anterior extremity of this, make transverse in- 

 cisions, and turn back the flaps of muscle. 

 Without disturbing anything, note in the abdo- 

 minal cavity thus laid open : 



145. The peritoneum, a moist shining membrane, 

 lining the whole abdominal cavity. 



