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as is usual in these ganglia, are very small and not 
crowded, being scattered among the nerve fibres. 
The dorsal lateral line root, as already described, has 
a discrete ganglion, and a reference to the chart will show 
that the communis, ventral lateral line and motor roots 
enter the ganglionic mass above by two nerve bundles. 
The anterior one is the communis root and the posterior 
represents the ventral lateral line and motor roots fused 
together, the motor fibres of course having no connection 
with the ganglion cells. The entry of the trigeminus root 
into the Gasserian ganglion is described above. 
Leaving the compound ganglionic mass are three 
large nerve trunks: (1) the Truncus supraorbitalis; (2) 
the Truncus infraorbitalis; and (3) the Truncus hyo- 
mandibularis—all compound trunks into which both 
trigeminal and facial nerves enter. It will be seen on 
reference to the chart that the last is formed by three 
nerve bundles from the ganglionic mass uniting together. 
The most anterior of these arises from the Gasserian 
ganglion and thus forms the trigeminal cutaneous vii. 
component of the hyomandibular trunk. In Menzdia the 
cutaneous vil. is extracranial, and is formed by two 
bundles from the Gasserian ganglion fusing together. In 
the Plaice there are one large and two very small bundles 
—all intracranial. The middle of the three nerve bundles 
above is the communis root, and the posterior the fused 
ventral lateral line and motor roots. The motor vii., as 
mentioned above, joins the ventral lateral line root proxi- 
mal to the ganglionic mass. At first they remain distinct, 
the motor vii. lying on the outer face of the ventral lateral 
line ganglion. Before leaving the ganglion, however, the 
two roots become almost too intermingled to be 
distinguished. 
Before proceeding to describe the divisions of the vth 
