358 PROCEEDINGS OF THE CANADIAN INSTITUTE. 
With the infero-medial strand (7M.) issue the third and sixth 
nerves, the former being merely loosely attached to its medial aspect, 
the latter within its sheath along the ventral edge. With the 
supero-lateral strand issues the ramus buccalis, but in a separate 
sheath. 
Of the branches mentioned, the F&. buccalis, oticus, and ophthal- 
micus superficialis, can be traced directly to the roots from the tuber - 
culum acusticum ; their fibres are for the most part extremely broad, 
similar to those which form the auditory nerve, but some fine fibres 
are received from the dorsal geniculated root. To the latter are 
traceable for the most part the R. lateralis and ophthalmicus, as 
well as the infero-medial strand, while the supero-lateral strand is 
formed in great part by the broad motor fibres of the ascending and 
transverse root. (WV. V., asc. et trans.). The two principal roots thus 
assume a different relative position in the complex to what they 
have on emergence, immediately after which, indeed, they cross. It ~ 
is to be understood that neither the infero-medial nor supero-lateral 
‘strands are exclusively formed of fibres coming from one of the 
principal roots, but only chiefly so. The facialis, again, as it emerges 
from its foramen, although it contains all the broad fibres (13 p) 
which emerge as the motor root of the seventh, has also acquired 
fibres from the tuberculum acusticwm (10 ») and others of narrower 
diameter from the ganglionic complex, so that, although chiefly sup- 
plying the muscles of the palatine arches, the operculum and the 
hyoidean apparatus, it serves also as a path for fibres of different 
destiny. 
The auditory nerve (N. VIII., Figs. 14, 15 and 16, Pl. L.) leaves 
the tuberculum acusticum on a level with the motor root of the 
facial, and just behind that. Above it those fibres from the tuber- 
“culum acusticum which are destined for the vagus group, form a 
white band coursing backwards immediately under the crest of the 
tuberculum. (Fig. 3, Pl. V.). Almost immediately after its origin 
the auditory nerve divides into the shell-like ramus anterior, and the 
more cord-like ramus posterior, and indeed the cords of the latter, 
and the division between the anterior and posterior branches, may be 
carried very nearly up to the point of emergence from the brain. 
The fibres of the ramus posterior would seem to emerge somewhat 
higher than those of the ramus anterior. (Fig. 15, Pl. I.) 
