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of the fact that the large ventral nerve emerging from the 
Gasserian ganglion contains lateral line and communis 
components from the facial, the term 7’. mawillo-mandibu- 
laris, which refers to the unspht RR. maxillaris and 
mandibularis V, cannot strictly be applied to it. The 
cutaneous component of the trigeminus arises from the 
spinal v. tract, and its ganglion is the Gasserian ganglion. 
It is distributed to the skin of the face and operculum. 
The second root of the complex (r.1.vi.) belongs 
wholly to the facial, and consists of 3 roots so closely 
packed together that it is difficult to separate them by 
dissection. These roots are the dorsal and ventral lateral 
line roots and the communis root. The whole arise 
together at the same level high up on the medulla and 
much higher than and external to the exit of the 
trigeminus. The ganglia of the lateral line roots are 
respectively the dorsal and ventral lateral line ganglia, 
and that of the communis root is the geniculate gangiion. 
The dorsal lateral line root splits into the Ramus 
ophthalmicus superficialis vu. and the R. bucealis vii., 
whilst the ventral lateral line root is continued into the 
Truncus hyomandibularis as the R. mandibularis externus 
vu. The communis root splits into the communis v., R. 
palatinus vil., the R. Posttrematicus vil. and the R. 
mandibularis internus vil. Although the three com- 
ponents in this root are very compacted they retain their 
individuality under the microscope. The communis root 
enters the brain first, and then the other two fuse and 
enter together behind and above it. The communis root 
in the brain passes at once into the fasciculus communis 
tract, and the fused two lateral line roots terminate in the 
tuberculum aeusticum. 
The third root of the complex (r.2.vé.) is also 
entirely facial and constitutes its motor root. It arises 
