802 



PHYSIOLOGY OF THE DOMESTIC ANIMALS. 



-Diagram of a Spinal Segment as a Spinal Centre and Con- 

 ducting Medium, after Br am well. {Landois.) 



B, right, Bl, left cerebral hemispheres; M O, medulla oblongata; 1, motor tract from right hemi- 

 sphere, largely decussating at M O, and passing down the lateral column of the cord on the opposite side 

 to the muscles M and Ml ; 2, motor tract from left hemisphere ; S, SI, sensitive areas on the left side of 

 tho body ; 3, 3 1 , the main sensory tract from the left side of the body : it decussates shortly after enter- 

 ing the' cord ; S2, S3, sensitive areas, and 41, 4, tracts from the right side of the body. The arrows 

 indicate the direction of the impulses. 



