PREHISTORIC TIMES IN BRITAIN. 539 



to smaller structural peculiarities. The third molar consists of 

 three lobes ; but, large as is the jaw and the canine armature of 

 this SicSf the most posteriorly placed of the three lobes is more 

 simple than even the very simple posterior lobe of the pigmy Sus 

 andamauensis, having only one cusp prominently marked in the 

 upper, and four in the lower jaw, whilst the entire posterior lobe 

 is little, if at all, greater in antero-posterior extent, and much 

 smaller in transverse, than either of the anterior, diifering thus 

 altogether from Sns cristatus. 



A second point, relating to a small structure as measured by the 

 callipers, which is a very large one, however, to the morphologist, 

 is the permanent retention by Sms harbatus of the mesopterygoid of 

 Parker ('Phil. Trans.' 1874, p. 324, pi. xxxvi, fig. 4. ms.pg) as a 

 distinct bone. This peculiarity was observed in all the four skulls 

 of Su8 barbatus examined by me ; and its obvious general signifi- 

 cance is increased by the fact that it is in the area of the meso- 

 pterygoid that the great basicranial cavities are excavated in the 

 Babirussa and Phacochoerus, and are represented rudimentarily in 

 Sms vlttatus. 



Knowing what we do ^ of the affinity of the fauna of the sub- 

 region of Ceylon and South India to that of Malaya, there is no 

 a priori improbability in a view which should accept the Sus ceylon- 

 ensis of Blyth ^ (' Journal of the Asiatic Society of Bengal/ xx. p. 

 173) as identical with the Sus barbatus of Borneo. Mr. Blyth's 

 words, /. c., are as follows : — 



* Bus zeylanensis. Skull longer than that of the Indian boar, nearly straight in 

 profile, very much contracted at the vertex. Palate contracting posteriorly to less 

 than i" from the magnitude of the last molar, which is considerably larger in both 

 jaws than in the wild boar of India, the upper measuring i|" long by \%" broad 

 anteriorly. Vertex narrowing to 1" only in breadth. Total length of skull from 

 vertex to tips of nasals i6|". Altogether the skull approximates closely in contour 

 to the figures of the skulls of Sus barbatus by Dr. S. Miiller and M. Temminck.' 



Dr. Gray appears to have had access, which I have not had, to a 

 photograph of this Sus zeylanensis, and says that, judging from it, — 



•The skull is much shorter and thicker than the skull of 8. harbatus. The photo- 

 graph is much more like that of Sus verrucosus.^ 



For my own part, I cannot think Mr. Blyth would ever 4iave 



^ Tennant, 'Nat. Hist, of Ceylon,' pp. 61-68, 186 ; Wallace, * Geographical Distri- 

 bution,' i. p. 328. 

 ^ See Gray, 'Proc. Zool. Soc' 1S68, p. 24; 'Brit. Mus. Cat.' 1869, p. 331. 



