Herrick, Morpholoi^y of Brain of Bony Fislics. 215 



men it divides into two. A smaller branch turning caudo- 

 laterad passes to the masseter. The remainder passes through 

 the orbit to the angle of the mouth and infra-maxillary 

 region. The remaining fibres, which pass through the 

 foramen F.,, are those of V- and VII, which are inseparably 

 united for several centimetres. This trunk receives, in 

 addition to the fibres from V, and Vj, referred to above, a 

 small fascicle from V,,. After leaving the foramen a con- 

 siderable branch is given off from the cephalic division 

 which dips down and passes caudo-laterad to the depressor 

 operculi. The branches V. and VII subsequently partially 

 reunite before their final separation. This plexus may serve 

 the function of a chorda tympani. The more cephalic branch, 

 V5, is considered to be the homologue of the inferior maxillary 

 nerve. It gives off a few small fibres to the ental surface of 

 the masseter and then divides. The more superficial division 

 passes cephalad to the infra-maxillary region. The deeper 

 division passes through a foramen "in the articulare inferius 

 suspensorii maxillae (of Meckel) and again divides into a 

 dentary branch penetrating the end of the inferior maxillary 

 into its dental cavity and a mylo-hyoid branch which passes 

 by the end of the inferior maxillary, then cephalad on the 

 ventro-mesal surface of the latter to the inferior barbels, two 

 branches being given to each barbel. Ramus VII, which is 

 considered to be the homologue of the facial nerve, after 

 separating from V., passes laterad, giving off a twig to the 

 levator operculi. Passing then to the ventral surface, it 

 supplies the muscles of that region, apparently those con- 

 cerned chiefly with deglution. The carotid plexus, if present, 

 is probably all intra-foraminal. With reference to the first 

 four divisions of the fifth, homologies cannot be pushed very 

 far; and yet it seems legitimate to consider that the more 

 dorsal division of V, andV., are, roughly speaking, homolog- 

 ous with the orbito-nasal (of Parker), the rest of V,, V.., 

 and V4 with the superior maxillary. Two important divisions 

 of the fifth remain to be considered. The small branch V,. 



