76 LABORATORY OUTLINE OF NEUROLOGY 



('18), Fig. 86) and join the restiform body on its medial side. 

 Identify also the vestibule-spinal tract, passing toward the 

 spinal cord from the lateral and spinal vestibular nuclei. It 

 can be followed downward through the series of sections, ly- 

 ing in the angle between the restiform body and the dorsal 

 vagal nuclei (see Herrick ('18), Fig. 72). Learn its position 

 and enter it in the sketches of the medulla oblongata and cord. 



The superior and medial nuclei send fibers into the fasciculus 

 longitudinalis medialis (posterior longitudinal bundle, see Sec- 

 tion 92). Enter upon your drawings all of these vestibular 

 tracts which have been observed, including the fasciculus 

 longitudinalis medialis. See Bailey ('16), Fig. 339, p. 502; 

 Howell ('18), Chap. XXI, Jones ('18); Piersol ('16), Fig. 1071, 

 p. 1258; Quain ('09), Fig. 158, p. 141, and Fig. 181, p. 166; 

 Villiger ('12), Fig. 168, p. 182. 



We have now completed our first survey of the somatic 

 sensory systems of the spinal cord and the medulla oblongata, 

 except their connections with the cerebellum. These will be 

 taken up after the examination of the visceral sensory and 

 the motor centers of the medulla oblongata. 



84. Visceral sensory system. In the microscopic sections 

 identify and draw the fasciculus solitarius and its nucleus. 

 (See Section 62 (4) and (5)) . This fa*sciculus is made up chiefly 

 of root-fibers of the VII, IX, and X cranial nerves carrying both 

 general and special visceral sensory nervous impulses, the 

 special fibers being gustatory in function (Herrick ('18), Fig. 

 114). Root-fibers of some or all of these nerves may be seen in 

 the sections entering the fasciculus. They arise from the 

 geniculate (VII), petrosal (IX) and nodosal (X) ganglia. 

 Both the general and the special visceral sensory fibers end in 

 the nucleus of the fasciculus solitarius, the gustatory fibers 

 probably in its upper end. In the region of the ala cinerea 

 (Herrick ('18), Figs. 71 to 74) the nucleus is enlarged dorsally 

 and comes to the surface of the floor of the fourth ventricle at 

 the lateral border of the ala cinerea. The fasciculus solitarius 

 and its nucleus correspond with the visceral sensory column 

 seen in the brain of the dogfish (Section 23). For the dissec- 

 tion of the fasciculus solitarius in the human brain see Section 

 110, 



