JAW. 59 



of the lower jaw ; both of which, therefore, in extensive 

 motions of the jaw backwards and forwards, must move 

 together upon the temporal bone. 0. C. 261. 



Hunterlan. 



B. 56. The left ramus of the lower jaw, and part of the cranium 

 of a Porpoise (Plwccena plwccend). A section has been 

 made through the joint, to show the fibrous connecting- 

 substance in situ. 0. 0. 240 A. 



van Beneden, Arch, de Biol., t. iii. 1882, p. 669. 



B. 57. A section of the ligamentous substance that unites the 

 lower jaw to the cranium in the Whale. 0. C. 240. 



" The articulation of the lower jaw is not by simple contact 

 either single or double, joined by a capsular ligament, as in the 

 quadruped; but by a very thick intermediate substance of the 

 ligamentous kind, so interwoven that its parts move on each other, 

 in the interstices of which is an oil. This thick matted substance 

 may answer the same purpose as the double joint in the quadruped." 

 Hunter, Phil. Trans. 1787, vol. Ixvii. p. 384. 



Hunterian. 



B. 58. Half of the fibro-cartilaginous mass that formed the 

 squamoso-mandibular articulation of a young female 

 Balcenoptera acuto-rostrata. 0. C. 240s. 

 Perrin, Proc. Zool. Soc. 1870, p. 805. 



B. 59. The interarticular ligamentous substance from the joint 

 of the lower jaw of the Elephant (Elephas indicus). The 

 surface adapted to the temporal bone is concave in the lesser 

 and convex in the larger diameter ; the opposite or lower 

 surface presents a deep, oval excavation for the reception of 

 the condyle of the jaw. 0. C. 262. Hunterian. 



B. 60. A vertical section of the iiiterarticular substance from 

 the joint of the lower jaw of a younger Elephant, showing 

 the degree of concavity on each side, so well calculated 

 for adapting two convex surfaces to each other. A bristle 

 is placed in an orifice leading out of the lower cavity. 

 0. C. 263. Hunterian. 



