174 



EXPEKIMENTAL PHAKMACOLOGY 



lution. A deep blue color appears. Considerable mor- 

 phine produces a precipitate of Prussian blue. 



Potassium ferricyanide oxidizes morphine to oxy-dimor- 

 phine : 



2 CANO, + 2 KOH + K.Fe 2 (CN) 12 = 2H 2 O + (C 17 H 18 NO 3 ) 2 + 2K 4 Fe (CN). 

 Morphine Potassium Oxy-dimorphine Potassium 



ferricyanide ferrocyanide 



Potassium ferrocyanide then forms Prussian blue with 



Cerebrum 



Optic lobe 

 Cerebellum 



Semicircular 



canals 

 Medulla oblonqata 



Spinal cord 



Fig. 166. Posterior view of the brain and semicircular canals of a pigeon. 



Skin (cut) 



Cut edge of skull bone 

 Cerebrum 



Optic lobe 

 Cerebellum 



External ear 



Trachea 



Semicircular 

 canals 



Medulla 



pinal 

 cord 



Fig. 167. Lateral view of the head of a pigeon showing the brain, external auditory 



opening and semicircular canals. 



