328 BR. C. F. SONNTAG ON THE ANATOMY, 



has the usual sphincteric arrangement. From its deep surface it 

 chives oft' small muscular slips (text-fig. 27) which are attached 

 to the bones at the bases of the sockets of the incisor, canine and 

 premolar teeth. These are best developed in the upper jaw. 

 Between them and the mucous membrane there are numerous 

 labial salivary glands and branches of the infra-orbital nerve 

 plexus (text-fig. 26, I.O.P). 



Between the levator labii superioris and the levator anguli oris 

 numerous branches of the facial nerve and infia-orbital branches 

 of the trigeminal nerve ramify and anastomose, and numerous 

 labial salivary glands are present. The facial nerve supplies the 

 muscles, and the infra-orbital nerves can be traced to both skin 

 and mucous membrane. 



The levator anguli oris (text-fig. 26, L.A.O) is a small triangular 

 muscle. It arises from the maxilla below the infra- orbital fora- 

 men, and is inserted into the orbicularis oris at the angle of the 

 mouth. A small slip passes to the skin of the upper lip. The 

 latter is not mentionecl by other authors. 



The buccinator (text-fig. 26, Buc) arises from the maxilla and 

 mandible close to the roots of the last molar teeth and from the 

 pterygo-maxillary ligament. It emerges from under cover of 

 the ascending ramus of the mandible and blends with the orbicu- 

 laris oris in both lips; but the fibres do not decussate as in Man. 

 Lying on its surface are a pad of fat, several buccal salivai-y 

 glands, the buccinator branches of the internal maxillary artery, 

 and the long buccal branch of the trigeminal nerve. It is crossed 

 by the anterior facial vein and external maxillary artery. 



Nasal Muscles (text-fig. 27 A) : — No nasal cartilages exist*, so 

 the nasal muscles are inserted into the skin. The upper border 

 receives a continuous strip of muscles from the combined orbicu- 

 laris oculi and frontalis and the levator labii superioris. The 

 former corresponds to the pyramidalis (Pyr) and the latter to 

 the levator labii superioris alseque nasi (L.A.N). Three small 

 muscular slips arise from each half of the nasal orifice of the skull 

 and are inserted into the deep surface of the skin. No depressor 

 septi nasi is present. The sensory external nasal nerve is seen 

 emerging from the nasal fossa on each side. 



Extrinsic Muscles of the Auricle (text-fig. 25) : — Euge (42) 

 described and figured a superior auricular muscle descending 

 from the vertex of the skull to the root of the pinna, and auriculo- 

 occipital and posterior auricular muscles acting on its posterior 

 part. A small tragicus runs to the lower and front part of the 

 pinna. Wilder (53) described an attolens and a combined 

 attrahens and retrahens. In my specimen the attolens (AuR. 

 Ant) arises from the epicranial aponeurosis, and the combined 

 attrahens and retrahens (AuR. Post) arises from the aponeurosis 

 and occipital crest, touching the occipitalis above. The fibres 



* This statement is based on both macroscopic and microscopic examination. 

 But future material may show that the conditions here are purely individual in 

 character. 



