ACTION OF OPIUM ALKALOIDS 



173 



hut carefully save it until the next day observing it several 

 times in the meantime if possible. Do you note any 

 changes in the reflexes at any time? Does the frog re- 

 cover? What symptoms are exhibited during the recovery 

 period? How do you explain this? 



EXPERIMENT XXIII. 

 Thebaine, Codeine. (Frog: Central Nervous System.) 



Inject a frog with one cubic centimeter of two per cent 

 thebaine solution and a second animal with one cubic centi- 

 meter of two per cent codeine solution. Place the frogs on 

 moist cotton in a battery jar and watch the symptoms pro- 

 duced by the drugs. Compare these animals with the one 

 that got morphine. 



EXPERIMENT XXIV. 

 Morphine. (Chemical Test for Morphine.) 



1. Add a few drops of a dilute mixture of ferric chloride 

 and potassium ferricyanide solutions to a morphine salt so- 



N.I 



Olfactory nerves 

 Olfactory lobe 



Cerebral hemisphere 



N.n 



N.vr 



Ha Heck- 



optic 

 Hypophysis 



Optic lobe 

 Cerebellum 

 Medulla oblongata 



Spinal cord 



Fig. 165. Ventral and dorsal views of a pigeon's brain. (Modified from Wiedersheim.) 



