152 STRONG. [Vol. X. 



Facialis. — {a) What may be termed special ctitaneotis fibres, 

 i.e., those innervating the specialized lateral line sense organs. 

 These fibres are uniformly coarse and enter the dorsal part of 

 the medulla. There are two ganglia belonging to this com- 

 ponent. One, the ganglion of the Rr. opthalmicus superficialis 

 and buccalis (and oticus) facialis, has its permanent position 

 above the Gasserian ganglion proper and in contact v^rith it. 

 The other, the ganglion of the R. mandibularis externus VII, 

 is, in the tadpole, imbedded in the outer side of the Gasserian 

 ganglion, or rather between the latter and the ganglion of the 

 next mentioned component. In Amblystoma, however, this 

 ganglion has no relation to the Gasserian ganglion and lies 

 beneath the outer side of the auditory capsule ectad of 

 the ganglion of the next component and of the auditory 

 ganglion. 



{b) What may be termed the fasciculus comnmtiis com- 

 ponent. This innervates the anterior portion of the pharynx. 

 This component is composed principally of very fine fibres with 

 a number of slightly larger fibres interspersed ; it is derived 

 from Osborn's fasciculus communis. Further remarks upon 

 this tract and its distribution will be made elsewhere. This 

 component possesses one ganglion which is fused in the tadpole 

 with the ventral side of the caudal portion of the Gasserian gan- 

 glion proper. In Amblystoma, however, this ganglion has no 

 connection with the Gasserian and lies beneath the cephalic 

 end of the auditory ganglion. 



ic) Motor fibres in part similar to Trigeminus (b) and in 

 part derived directly from the posterior longitudinal fasciculus 

 (Osborn). 



Glossopharyngeus and Vagus. — (a) Geticral cutaneous fibres 

 similar to Trigeminus {a) and derived from the ascending 

 Trigeminus. The ganglion of this component is a portion of 

 the mass of ganglion cells on the trunk of the IX + X nearest 

 the medulla (ganglion A). 



{b) Special cutaneous fibres similar to Facialis {a) in every 

 respect and passing into the Rr. laterales. The ganglion of 

 this component lies in the dorsal part of the ganglionic mass 

 just mentioned {i.e., of ganglion A). 



