Respiratory System and Alimentary System {continued). 



1. Remove the mylo-hyoid muscles to expose the hyoid apparatus. Pass 

 a seeker through the glottis to one of the lungs and slit it open with a pair 

 of scissors. Examine the structure of the lung. 



2. Remove the whole of the alimentary canal with the lungs, liver, pan- 

 creas, and spleen, by cutting through the oesophagus and the large intestine 

 before it joins the cloaca, and detaching it from the roof of the body cavity 

 without injuring the kidneys and the reproductive organs. 



Draw the complete alimentary canal. 



Entrance of Bile duct 

 into Duodenum 



Cloacal aperture 



Fig. 8.— Alimentary Canal of Xenopus and Rana. 



Urinogenital System. 



Note the kidneys, two elongated, flattened, dark-red bodies lying one 

 on each side of the vertebral column towards the posterior end of the abdo- 

 minal cavity. From the outer edge of each kidney a ureter arises and runs 

 backward, opening into the cloaca on the dorsal side, opposite the opening 

 of the urinary bladder. 



[In the Frog the adrenal bodies may be seen on the ventral sides of the kidneys 

 as small yellow patches.] 



24 



