ANATOMY OF THE LUNGS 179 



solution; gently scrape with scalpel and examine scrapings 

 under microscope. 



4) Remove from rabbit its abdominal viscera, cutting away 

 liver and stomach with especial care. Examine vaulted 

 diaphragm and through it the lungs. 



5) Seize diaphragm by its centre and pull it down, imitating 

 its respiratory movements. 



6 ) Make a free opening into first one and then the other side 

 of chest and note effect upon lungs. 



7) Cut away front of chest and observe tendinous centre 

 of diaphragm ; its muscular periphery ; and attachment of peri- 

 cardium to its thoracic side. 



8) Place a recently killed frog on its back; fasten lower jaw 

 wide open. 



a) Place small object on roof of mouth near nose and note 

 movement. 



b) Examine scrapings from roof of frog's mouth in normal 

 salt solution under microscope. 



9) Remove as much of esophagus as possible; split it open 

 and pin out. 



a) Place small object upon it near mouth and note behavior. 



b) Set esophagus aside under moist glass and note position 

 of mucus on surface at end of half an hour. 1 



Respiration 

 Materials : 



Blood clot, defibrinated blood, or piece of liver; lungs of 

 rabbit, cat, or rat; phenolphthalein (a few drops 1 per cent 

 solution ) ; lime water ; thermometers in tin cases ; mirror ; tape 

 measure; wide-mouthed bottles; bottle of 1 gal. capacity; pan 

 for water; test tube; glass tubes; rubber tubing; bell jar of 

 2 qts. capacity; heavy pure gum sheet rubber, to tie over 

 bottom of bell jar; pinchcock; rubber stopper with double 

 perforations, to fit bell jar; 2 pieces of glass tubing, to fit 

 perforations of stopper ; water-valve respiration apparatus for 

 carbon dioxide. 



1) Note the effect of breathing on bulb of a thermometer; on 

 a mirror, knife blade, or other polished metallic surface. 



1 Cilia are present in the respiratory passages but not in the 

 esophagus of man. 



