LABORATORY MANUAL OF PHYSIOLOGY. 



IV. REMOVAL or THE CEREBRUM IN A PIGEON. 



Remove the cerebral hemispheres in a pigeon anaesthetized with 

 ether. Sew skin over wound. Allow the pigeon twenty-four hours 

 to recover from the effect of the operation. Compare the pigeon 

 so treated with a normal bird. Is there any disturbance of co-or- 

 dination ? Is the pigeon able to sit on a perch ? Is it able to fly ? 



V. REMOVAL OF THE CEREBELLUM OF A PIGEON. 



Etherize another pigeon. Remove the bone of the skull over the 

 cerebellar region, leaving a bony bridge in the middle line. Go in 

 from either side with a blunt instrument. Sew skin over wound 

 and allow twenty-four hours for recovery from the shock of the 

 operation. 



How does this pigeon compare with the normal and with the one 

 which has had its cerebrum removed? Describe all phenomena 

 and reactions to various stimuli. Are there any disturbances of co- 

 ordination ? If so, what are they ? 



VI. HEMISECTION OF THE SPINAL CORD. 



Narcotize a dog or a rabbit with morphine and ether. Cut off 

 hair of back in upper lumbar region. Make a longitudinal incision 

 through the skin and muscles over the spinous processes of the first 

 three vertebra. Cut through the spinous processes with bone-scis- 

 sors. Clean the lamina? of muscle. With a small trephine, care- 

 fully remove a button of bone from the lamina of one side. From 

 this opening remove the rest of the lamina with fine bone-cutting 

 forceps. This will expose the cord in its membranes. Make an 

 incision through the membranes with fine-pointed scissors. With a 

 fine sharp scalpel cut through one-half of the cord. After any en- 

 suing hemorrhage has been controlled, sew up the wound with cat- 

 gut or silk. Allow the animal twenty-four or thirty-six hours to 

 recover from the shock of the operation and then make observa- 

 tions on the affected side compared with the other for changes in 

 voluntary motion and sensation. Test the various reflexes also 



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