156 ANATOMY OF VERTEBRATES. 



then, continued forward, superficially, along the slender jugal 

 bone, toward the eye-opening, supplies the ' angularis oculi pos- 

 ticus,' and the muscles of the under eyelid : in advance of this it 

 supplies the ( angularis oculi externus,' and forms a large plexus, in 

 connection with branches of the trigeminal. From the plexus pass 

 filaments to the muscles of the blow-hole and its plicated sacs. 



In Mammals with a well developed parotid the facial traverses 

 that gland; it divides there into three principal branches in the 

 Calf 1 and Dog; 2 whilst in the Hog, the trunk is continued 

 forward to near the fore part of the masseter, before dividing into 

 maxillary and mandibular portions, and the auriculo-palpebral 

 branches come off more separately from the long trunk. In 

 Quadrumana, as in Man, the chief branching of the trunk takes 

 place at the hind margin of the masseter after the post-auricular 

 nerve is sent off: from the upper of the main divisions pass the 

 nerves to the temple and eyelids as well as to the nose and upper 

 lip. A slight enlargement of the facial near its entry into the 

 e fallopian aqueduct '- -its petrosal canal is called f geniculate 



a-ano-lion ' which receives a petrosal branch of the vidian nerve, 







and one from the superficial petrosal which unites the otic gan- 

 glion with the tympanic nerve. Prior to the ganglion the facial 

 is connected by one or two filaments with the acoustic nerve : be- 

 yond the ganglion it receives a petrosal filament of the sympathetic. 

 The ' chorda tympani,' fig. 259, c, leaves the trunk of the facial 

 before it quits its canal, enters the tympanum, crossing the tym- 

 panic bone and the ear-drum, behind the handle of the malleus, b, 

 to emerge by an aperture at the inner end of the ' glaserian 

 fissure:' then passing downward and forward it joins the gusta- 

 tory. In the Horse and Calf I traced, in 1836, 3 the superficial 

 petrosal branch, or backward continuation of the vidian nerve, 

 fig. 132, li, into the seventh, penetrating its sheath, but remaining 

 distinct, and separating into many filaments, ib. b, with which 

 filaments of the seventh nerve, ib. b, k,f, are blended, and a 

 ganglion formed, ib. ^7, by the superaddition of grey matter ; the 

 chorda tympani, ib. m, is here continued partly from this ganglion, 

 partly from the seventh or portio dura, ib. 6. I did not at that 

 time distinguish the fasciculus, b, called ( portio intermedia ' of 

 the facial from the main trunk, a. The chief point, however, as 

 to the ( chorda tympani' not being a branch of that main trunk 



1 LIV. pi. xxx. fig. 3. 2 Ib. fig. 2. 



3 In reference to the expression of Hunter, relative to the chorda tympani, ' I am 

 almost certain it is not a branch of the seventh pair of nerves, but the last described 

 branch from the fifth pair.' xciv. (1837) p. 194, and ' Note a.' 



