152 



INTRODUCTION TO NEUROLOGY 



Lobus lines latcralis 



Fasc. long, med 

 Lobus visceralis 



-J 



Fig. 68. The medulla oblongata and cerebellum of the lake sturgeon 

 (Acipenser rubicundus) to show the longitudinal columns which have been 

 differentiated in correlation with the peripheral functional systems. Com- 

 pare Figs. 43 and 44 and note that the "Lobus lineae lateralis" and "Tu- 

 berculum acusticum" of this figure together correspond to the "acoustico- 

 lateral area" of the dogfish. A is a dorsal view with the membranous roof 

 of the fourth ventricle removed to show the longitudinal columns within 

 the ventricle. B, C, and D are sketches of cross-sections at the levels 

 indicated in which the four functional columns are diagrammatically shaded, 

 the somatic motor by white circles, the visceral motor by white rectangles, 

 the visceral sensory by oblique cross-hatching, and the somatic sensory by 

 vertical cross-hatching. The Roman numerals refer to the cranial nerves. 

 (From Johnston's Nervous System of Vertebrates.) 



