544 



THE NERVOUS SYSTEM 



cord and is supposed to furnish motor innervation to the long muscles of the 

 trunk. 2. The antero-lateral group of cells, 2a, forms a column which has 

 its best development in the cervical and lumbo-sacral enlargements. It 

 probably furnishes motor fibers to the muscles of the limbs including those 

 of the shoulders and hips. 3. There are groups, 2b, 2c, the intermedio and 

 lateral groups, which form slender columns in the cord, through the entire 

 dorsal and the first two lumbar segments. The cells are small and closely 

 aggregated and characteristic in appearance. These nuclei reappear in the 



FIG. 361. From the Lower Lumbar Cord of Man, after a Preparation by Klonne and 

 Miiller stained by Weigert and Pal's method. A portion of the gray substance of the 

 anterior column with the adjoining portions of the lateral funiculus is represented, showing 

 anterior column cells and the fine medullated fibers which enter the gray substance from the 

 lateral funiculi and surround the nerve cells, which here are provided with fine pigmented 

 granules. High power. (Kolliker.) 



upper cervical segments and in the sacral segments that give origin to the 

 nervi erigens. They are supposed to be the motor nuclei for the vaso-motor, 

 the pilo-motor, and the nerves of the sw r eat glands, i.e., the autonomic system. 

 4. The cells of the posterior vesicular column, or Clark's column, are in the 

 posterior portion of the gray matter of the cord. They form a conspicuous 

 column of cells, 3, 5, and 6 of figure 362, extending from the last cervical to the 

 second lumbar segments. These large cells contribute their axones to the 

 ascending cerebello-spinal (direct cerebellar) fasciculus which ascends to the 

 cerebellum and is believed to carry sensory impulses of prime importance in 



