of tigroid substance representing much expenditure of energy 

 here. The large size of the neurone is evidently the correl- 

 ative of the iuiportiince which the system assumes in the inner- 

 vation of great vital organs. Such innervation requires a 

 nexus with viscero-sensory neurones, and the means have already 

 been suggested in the preceding subsection, the interlacing 

 of the axones from the lobus vagi with the dendrites of the 

 viscero-motor nucleus. 'This gives a complete reflex circuit 

 for visceral innervation. 



6. Gen.eral Cutaieous h'ucleus and Spinal V Iract. 

 The literature of the portion of the oblongata included 

 here is in some confusion.. The older writers did not have 

 methods of investigation which would demonstrate the presence 

 in this region of several important groups of neurones. They 

 did see that it contains nunerous bundles of nerve-fibres, 

 however, some of which run to the cerebellum, and so peduncu- 

 lus cerebelli appeared to be a perfectly satisfactory designa- 

 tion. Kingsbury )'97) extended the term spinal 7th tract to 

 both the nuclei of the region and the trigeminal fibre-tract 

 proper; such use of a term originally intended to designate 

 a definite group of nerve-fibres is certainly to be avoided 

 as leading to confusion. Johnston ('99b) appears to include 

 a part of this region under his tuberculwr acusticum. Since 

 there appears to be need for a precise terci which shall desig- 



