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end of the otic capsule. No ganglion cells could be found in the nerve, 

 after its origin from the ganglion, either inside or outside the 

 cranium, and I accordingly at first took it to be the motor facialis 

 nerve of von Kupffer's descriptions. But as certain of its terminal 

 branches may be sensory, it may contain the sensory component 

 that has its origin from von Kupffer's 6th epibranchial ganglion, 

 that ganglion having become so intimately related to the acusticus 

 ganglion as not to be distinguishable from it in the sections. The 

 resulting ganglion is a disc-shaped structure that lies close against 

 the lateral surface of the medulla, wholly internal to the membranous 

 cranium. Its anterior end extends forward almost to the level of the 

 hind end of the maxillo-mandibularis ganglion, and there lies between 

 the buccalis lateralis and motor trigeminal roots. The ganglion, in 

 its middle and widest portion, covers the entire lateral surface of the 

 medulla, and is closely pressed and flattened out against the medulla. 

 Its roots could not be satisfactorily determined in any of my sections, 

 but there are certainly two roots, one dorsal and the other ventral. 

 The fibres of the ventral root, or at least a considerable part of them, 

 simply traverse the ganglion and go directly into the trunk of the 

 facialis. The dorsal root has an apparent origin similar to that of 

 the root of the buccalis lateralis. 



From the ventral edge of the ganglion three nerves arise, which 

 together form the nervus acusticus, each nerve separating into two 

 branches. These branches pierce separately the membranous mesial 

 wall of the otic capsule, and are doubtless destined to supply the 

 auditory sense organs only, but certain of them could not be definitely 

 traced to those organs. The ductus endolymphaticus also pierces the 

 membranous cranial wall of the otic capsule, and running upward and 

 slightly forward ends close against the lateral surface of the medulla, 

 immediately behind, or perhaps even lateral to, the hind end of the 

 acustico-facialis ganglion. 



The nervus facialis, as it issues from the cranium, lies, as already 

 stated, in a posterior continuation of the membranous chamber that 

 encloses the trigeminal ganglia. That chamber ends, as a closed 

 chamber, posterior to the hind end of the maxillo-mandibularis gan- 

 glion. The roof of the chamber there dissolves, so to speak, and is 

 replaced by scattered fibrous tissue. The lateral wall of the chamber, 

 however, persists, and, in the region where the facialis issues from the 

 cranium, becomes again connected both dorsally and ventrally with the 

 membranous side wall of the skull; a posterior continuation of the 

 trigeminal chamber thus being formed. Having entered this chamber 



