100 SPECIAL ANATOMY. 



113. c. The Atlas with the Epistropheus, or vert, dentata. 



1. Rotary articulation trochoides between the anterior arch 

 of the Atlas and the Odontoid process which last describes on 

 each side within a ring, anteriorly osseous, posteriorly ligamentous 

 (Lig. transvers.}, the fourth part of a circle, and prevents every 

 other movement but rotation which is performed by the proc. 

 obliq. inferr. atlant. and superr. epistroph., as the atlas and cra- 

 nium move thereon as one piece. 



2. Between proc. obliqui atlant. and epistrophei a free articu- 

 lation arthrodia since the circular surfaces of both planes lie 

 horizontal, and are provided with a wide articular and synovial 

 capsule. 



3. Lig. transversum ailantis, very thick and dense, flat, extending horizon- 

 tally behind the Odontoid process, from one lateral mass of the atlas to the 

 other. The anterior concave surface is in apposition with the posterior surface 

 of the Odontoid process, which is covered with cartilage. [In the centre of 

 this transverse ligament there is a portion of cartilage, and a very delicate 

 synovial capsule is attached around the articular surfaces.] From the supe- 

 rior border an appendix passes upwards to the anterior border of the foram. 

 magnum ; a similar from the inferior border to the posterior surface of the 

 Corpus epistrophei; thence arises a ligarn. crudatum. 



114. Articulation of the lower jaw, arliculatio maxillaris, a 

 free joint, formed 



1. By the elongated proc. condyloid. of each half of the lower 

 jaw, covered with cartilage, which is directed rather obliquely 

 from without to within from before to behind ; and 



2. By the deep and capaciousybs.ser, glenoidalis of the temporal 

 bones, the anterior part of which, to \hefissura G/aseri, is alone 

 covered with cartilage, and is an articular cavity. The anterior 

 wall forms the convex transverse root of the proc. zygomatic., 

 and upon it the proc. condyloid. , likewise convex, rolls backwards 

 and forwards. 



Between the articular surface lies a free 



1. Meniscus [or interarticular cartilage], firmly attached below, to the Con- 

 dyle, behind, to the glenoid cavity, dividing the articular cavity into a supenor 

 and inferior space. 



2. Ligam. capsulare extends from the bor:ler of the fossa glenoid. to the cir- 

 cumference of the Condyle. Above and below the cartilage lies a synovial 

 capsule ; the superior is wi !er, and proceeds from the boundary of the Cavit. 

 glenoidal. and tvberc. ariiculare, the inferior from coHum condyli. 



3. Lig. lalerale externum, from the tvberrle at the root of the Prnc. zygomat. 

 to the outer side of the Collurn Condylt, triangular and broad ; it covers the 

 outer si;le of the joint. 



4. Lig.lateraleinternum,fcom Spinaangvlaritofthe Sphenoid bone to theosseus 

 lamelhe on the inner side of the foram. maxill. post., separates the dental vessels 

 and nerves from the muse, p .erygoid., is thin and broad, contributing little to the 

 strength of the joint; likewise the so-called Lig. slylo-incmllarc, merely lascia. 



