THE MEDULLA. 



97 



through studies of Pincus, of Cole, and especially of Oliver S. Strong. It 

 has been demonstrated that all of these animals possess a sensory portion of 

 the Nervus facialis which innervates this canal-system of the head. Similar 

 apparatus on the trunk receive principally branches from the Vagus. From 

 ■what part of the brain the sensory portion of the Facialis arises is uncertain. 

 Further investigation is necessary. Strong maintains that the Tuberculum 

 acusticum comes into consideration. To the author it seems more probable 

 that we have to do here with parts which have been previously attributed 

 to the terminal apparatus of the Trigeminus. In all teleosts there is, in con- 

 nection with the terminal nucleus of the Trigeminus, a large lobe which, in 

 cyprinoids and other fishes, is connected with that of the opposite side, and 

 is located transversely over the ventricle. Powerful bundles of fibres — desig- 



Tuberculuin acust 

 et acusticus Held 



Tract. N. trig, exl 

 loboj 



Wervus cochlearis i 



/Decussat. bet. the 

 ^ tub. acu3C. 



f Diverticulum ven- 

 (. triculi 



("Tr. acustico-tect. 

 t dorsales 



fFasc. longit. post. 

 \ et Tr. tecto-spin. 

 fTr. vago-cerebel- 

 t laria 



>fucl. N. facial. 

 Tr. assoc. breves 



Fig. 54. — From the medulla of Barbiis fluviatilis ; Vagus and Trigeminus roots. 



nated in the figures as "Bad. lobares N. trigem." — pass out of the Lobus 

 trigemini. Should further investigation substantiate the author's supposi- 

 tion that we are dealing here with the terminal nucleus of the sensory Faci- 

 alis, then the names, in the Lobus Kervi facialis will have to be changed. 

 What is designated (Fig. 54) as Tracius Nervi trigemini ex loho probably 

 represents the sensory Facialis. But, without doubt, the origin of the 

 nucleus requires, in lower vertebrates, to be most carefully studied anew. 



Figs. 53, 53, and 64 will elucidate the point better than a description. 



In birds and, especially> in the armored reptiles the frontal nucleus 

 of the Trigeminus is much less developed than in other animals. With each 

 Nervus trigeminus there passes a fasciculus from the brain, which origi- 

 nates from the roof of the midbrain. This Radix mesencephalica trigemini 

 arises from large, pear-shaped cells, which lie near the aqueduct in mammals. 



