8 



2. The small intestine. Prepare and examine a piece. Note — 

 (a) The villi, minute processes of the mucous membrane. 



(6) Peyer's patches, of a honey-combed appearance, occurring at 

 intervals along the whole length of the small intestine on its free 

 margin. 



3. The caecum. Eemove it from the body ; slit it open longitudinally, 



and note — 



(1) The internal papillose surface. 



(2) The prominent spiral fold. 



(3) The openings of the sacculus rotundus and the colon. 



(4) The inner surface of the vermiform appendix, similar to a Peyer's 



patch. 

 4t. The colon. Slit it open ; note the papillose surface and the saccula- 

 tions. 

 5. The rectum. Note its smooth mucous lining. 



D, The Thoracic Viscera. 



Open the thorax by a longitudinal incision on each side of the sternum, 



and remove, the sternum with the attached portions of ribs. 

 Note the following parts in position — 



1. The thymus gland, variable in size, in the anterior part of the thorax. 



2. The heart and pericardium. 



3. The lungs, trachea, and bronchii, the left lung divided into two lobes, 



the right into four. Inflate the lungs from the trachea. 



4. The diaphragm, with its central tendon and its two posterior muscular 



crura. 



5. The phrenic nerves, lying between the heart and the lungs, and divid- 



ing posteriorly to supply the diaphragm. 



6. The pleurae, lining the cavity of the thorax and reflected over the 



lungs, forming two sacs, one on each side with a space between (the 

 mediastinum). 



7. The oesophagus, running in front of the back bone and piercing 



the diaphragm. 



E. The Circulatory System. 



Remove the thymus gland, expose the heart and the roots of the great vessels. 

 The heart and great vessels. Note — 



1. The heart, conical in form, with its apex or ventricular portion 

 directed backwards and to the left, and its base or auricular portion 

 forwards, 

 (a) The left ventricle, forming the apex and left side of the ventricular 



portion. 

 (6) The right ventricle, forming the right side of the ventricular 

 portion, but not reaching to the apex. 



