THE OPTIC THALAMI 



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are mixed. Each is separated by the anterior limb of the internal 

 capsule into two divisions, external and internal, known respec- 

 tively as the lenticular and caudate nuclei. (See Fig. 80.) 



FIG. 80. Human brain, with the hemispheres, removed by a horizontal 



incision on the right side. 



4, trochlear; 8, acoustic nerve; 6, origin of the abducens; F, A, L, position of the 

 pyramidal (motor) fibers for the face, arm and leg; S, sensory fibers. (Landois.) 



The optic thalami, one on either side, have an oval shape and 

 rest upon the crura cerebri between the posterior extremities of 



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