GENERAL SURVEY OF THE FROG 13 



Draw a diagrammatic cross-section through the frog at the level of the 

 stomach. This diagram must include the skin, the subcutaneous lymph spaces, 

 the vertebral column and contained spinal cord, the cisterna magna and its 

 contents, the stomach, duodenum, pancreas, tips of the lobes of the liver, repro- 

 ductive organs and their ducts, and the relation of the peritoneum and the mesenteries 

 to these organs. This drawing is to be constructed from the knowledge gained 

 from the foregoing examination of the frog. Holmes, Fig. 12, may be consulted 

 but is not to be copied. 



The general anatomical features and relations expressed in such a diagram 

 are those common to all vertebrates (except the subcutaneous lymph sacs). 

 The general systems of organs are common to all animals except the lowest, 

 although the details vary considerably. 



