CUTANEOUS NERVES. 23 



a communication is established between this and the facial nerve. Fi- 

 nally the nerve ends in two cutaneous branches, which ramify in the tegu- 

 ments : 



One of these (inner) soon pierces the occipito-frontalis, and reaches 

 upwards as high as the parietal bone. The other branch (outer) is of 

 larger size, and, perforating the muscle higher up, extends over the arch 

 of the head as far as the ear. 



As the nerve escapes from the supra-orbital notch it furnishes some 

 palpebral filaments to the upper eyelid. 



At the inner angle of the orbit is the small supra-trochlear branch 

 (fig. 2, 5 ) of the same nerve. It ascends to the forehead close to the 

 bone, and piercing the muscular fibres ends in the integument. Branches 

 are given from it to the orbicularis and corrugp.tor supercilii, and some 

 palpebral twigs enter the eyelid. 



The superficial temporal nerves are derived from the second and third 

 trunks of the fifth nerve, and from the facial nerve. 



The temporal branch of the superior maxillary nerve (second trunk of 

 the fifth) is usually a slender twig (fig. 2, 10 J, which perforates the tempo- 

 ral aponeurosis about a finger's breadth above the zygomatic arch. When 

 cutaneous, the nerve is distributed on the temple, and communicates with 

 the facial nerve, also sometimes with the next. 



The auriculo-temporal branch (fig. 2 d) of the inferior maxillary nerve 

 (third trunk of the fifth) lies near the ear, and accompanies the temporal 

 artery to the top of the head. As soon as the nerve emerges from beneath 

 the parotid gland, it divides into two terminal branches : The more pos- 

 terior is the smaller of the two, and supplies the attrahens aurem muscle 

 and the integument above the ear. The other branch ascends vertically 

 in the teguments to the top of the head. The nerve also furnishes an 

 auricular branch (upper) to the anterior part of the ear above the audi- 

 tory meatus. 



The temporal branches of the facial nerve are directed upwards over 

 the zygomatic arch and the temporal aponeurosis to the orbicularis palpe- 

 brarum muscle : they will be described with the dissection of the trunk of 

 the facial nerve. 



The posterior auricular nerve (fig. 2, *) lies behind the ear with the 

 artery of the same name. It arises from the facial nerve close to the 

 stylo-mastoid foramen, and ascends in front of the mastoid process. Soon 

 after the nerve becomes superficial it communicates with the great auri- 

 cular nerve, and divides into an occipital and an auricular branch, which 

 are distributed as their names express : 



The occipital branch is long and slender, arid ends in the posterior 

 belly of the occipito-frontalis muscle. It lies near the occipital bone, 

 enveloped in dense fibrous structure, and furnishes offsets to the integu- 

 ments. 



The auricular branch ascends to the back of the ear, supplying the 

 retrahent muscle and the posterior surface of the pinna. 



The great auricular nerve of the cervical plexus (fig. 2, l ) is seen to 

 some extent at the lower part of the ear, but its anatomy will be after- 

 wards given with the description of the cervical plexus. 



The great occipital (fig. 2, 3 ) is the largest cutaneous nerve at the back 

 of the head, and is recognized by its proximity to the occipital artery. 

 Springing from the posterior primary branch of the second cervical nerve, 

 it perforates the muscles of the back of the neck, and divides on the occi- 



