430 Journal of Comparative Neurology and Psychology. 



Fig. 7. A horizontal longitudinal section through the medulla oblongata of an adult Ameiurus 

 nebulosus about 20 cm. long, stained by the method of Weigert-Pal. X 2.3. 



The section is somewhat oblique, the left side being further dorsad than the right side. On the right 

 side the spinal V tract is seen terminating. in its own nucleus and also sending strands into the median 

 funicular nucleus. The lateral funicular nucleus lies farther dorsally, its apes being shown on the left 

 side. On the right side the fibers of the dorso-lateral fasciculus for this nucleus are seen descending along 

 the outer border of the spinal V tract at f.d.l. {cf. Fig. 5). The commissural nucleus of Cajal is cut 

 through its dorsal port. It receives afferent fibers from the most caudal vagus root and from the vagal 

 lobes above — descending secondary visceral tracts. Its commissure at this level contains but few medul- 

 lated fibers. The efferent tracts from the commissural nucleus do not appear so far dorsally as this 

 section. 



asc.sec.VII., ascending secondary gustatory tracts from the facial lobe; asc.sec.X., ascending secondary 

 gustatory tracts from the vagal lobe; com.r.VII., communis root of the facial nerve; com.s.gust.n., com- 

 missure of superior secondary gustatory nuclei; desc.sec.VII., descending secondary gustatory tract 

 from the facial lobe; desc.sec.X., descending secondary tracts from the vagal lobe to the commissural 

 nucleus of Cajal; f.d.l., fasciculus dorso-lateralis; n.jn.L, lateral funicular nucleus; nf.n.m., median 

 funicular nucleus; n.sp. F., spinal F nucleus; r./f.j?^., descending sensory root of the vagus; r.lat.VII. 

 lateral line root of the facial nerve; r.lat.X., lateral line root of the vagus nerve: r.V., root of the trigem- 

 inus nerve; r.JT., chief sensory root of the vagus nerve; s.geL, substantia gelatinosa Rolandi; s.gust.nuc. 

 superior secondary gustatory nucleus (n. lateralis cerebelli, n. visceralis cerebelli, Johnston); sp.V.lr., 

 spinal V tract; tuh.ac, tuberculum acusticum; vhc.com.nuc, visceral commissural nucleus (nucleus of 

 Cajal). 



