DB. J. MUEfE ON THE ORGANIZATION OF THE CAAING WHALE. 253 



and between it and the gums, there is a smooth shallovr' gutter an inch broad. The 

 anterior third of the mid palate is coriaceous, rough, and bestrewed with hardened, 

 closely placed papillae, which are arranged in irregular linear rows. In the median line, 

 however, this rough patch is longitudinally bisected by a narrow shallow sulcus, which 

 is lost behind in the smoother palate ; but anteriorly it sinks deeply between the pre- 

 maxillary bones, and there its edges are firmh adherent to the periosteum. Quite at the 

 back of the palate, or faucial portion, there is a smooth whitish-coloiu-ed area narrowest 

 forwards ; and on either side of this are numerous openings of muciparous ducts. 



The dental formula in this specimen may be expressed by jjEio- The last left lower 

 tooth was very small. The mandibular teeth increased in size from the first to the 

 sixth, again decreasmg in magnitude posteriorly ; nearly the same ratio obtained in 

 those of the upper jaw, where the teeth are less curved. I noted that the sixth tooth 

 of the mandible, the largest in the series, had an elevation of 0'4 inch above the gum, 

 and the final one of the same row but 0T5 inch. The superior maxillary teeth were set 

 with tips recurved, and inwards and dowTiwards ; the mandibular series agreed as to 

 postero-inward inclination. The length of the lower dental row was 6 and 6J, and of 

 the upper 5^ and 5^ inches respectively. The conical teeth were implanted in deep 

 sockets, but nevertheless they possessed a certain amount of mobility when pressed 

 laterally by the hand. This slight looseness, even in adolescence, may account for 

 individuals, both young and old, losing them, as authorities record. 



The mucous membrane of the gums is continuous with the palatine tissues, but is 

 lighter coloured. It embraces the necks of the teeth circularly, and runs between 

 each dental interspace as a longitudinal ridge. Outside the gums and teeth, or labially, 

 the membrane returns to its dark colour, and intensifies as it approaches the jet-black 

 surface of the skin of the body. The portion which corresponds to the upper lip slopes 

 gradually downwards and outwards, so as to form an eave or firm overhanging arch. 

 This is deepest behind at the angle of the mouth, and becomes by degrees less so, until 

 anteriorly reaching what represents the frsenum labii superioris, where it is but very 

 slightly elevated above the palate. The maxillary labial border projects sufficiently to 

 overlap and partially hide the mandibular one, when the mouth is closed. 



The inner surface of the lower jaw shelves rather abruptly downwards. It is narrow 

 and dark-coloured, towards the teeth inwardly smooth, from that rough as far back as 

 the teeth go. The gingival membrane, like the maxillary arch, is light-hued and rises 

 round the dental necks. So suddenly and perpendicularly does the outer smooth and 

 jet-black mandibular surface rise, that there is no defined lower lip or ridge whatsoever. 



There is no clearly marked dependent uvula' ; but the posterior pillars of the fauces 



prominently arch over the root of the tongue by the great thick palato-glossus. When 



the mouth is fuUy agape, the loose folds of the mucous membrane form lateral segments 



of arches, the middle or keystone dividing these by short, somewhat longitudinal, 



' A condition likewise mentioned by Profesaor Maoalister, P. Z. S. 1867, p. 478. 



2o2 



