256 HEMISECTION OF BRAIN. 



11. The tenth pair pass down out of the brain cavity, give 

 off branches to the pharynx and larynx, and are distributed to 

 the heart, lungs, and stomach; hence the name Pneumogas- 

 tric Nerves. 



12. The last pair of cranial nerves, the twelfth, arise near 

 the middle line of the spinal bulb. This pair supply the 

 muscles of the tongue, and are called the Hypoglossal Nerves. 



Cerebrum 



Spinal Bulb 



Fig. 79. Vertical Section of Brain. 



Draw the brain as seen from below, showing all these nerves. 



Separate the cerebral hemispheres, and with a sharp knife 

 split the brain lengthwise in the middle line. Make a draw- 

 ing of the inner face of one half. Note the branched appear- 

 ance, the Arbor Vita, of the cerebellum. Trace the cavities of 

 the brain. 



