286 



ON THE DOMESTIC PIG OF PREHISTORIC TIMES IN BRITAIN. 



Measurement of Skull of Sus barbatus, 



inches 



Extreme length 19'7 



Height 6-7 



Base-line 167 



Length of nasals from plane of postero- 

 lateral tips 10 - 5 



Fronto-parietal region in vertical aspect 

 from same point as preceding mea- 

 surement to occipital ridge in straight 



line 9-0 



Width of nasals 15 



Maximum (interzygomatic) width . 6 - 8 



1519 d, Oxford University Museum. 



inches. 

 Maximum frontal (interectorbital) 



width 4'5 



Minimum vertical l - 4 



Lacrymo-malar line 1*2 



Height of lacrymal 1*2 



Length of posterior upper molar . . ] -4 

 Breadth of anterior, which is much the 



widest lobe - 9 



Length of posterior lower molar . . T5 



Breadth of anterior lobe 0"8 



Intermolar space at narrowest point . 1*1 



Fig. 8. Left lower third molar of Sus andamanensis, female, 2\ times the natural size. 



This tooth shows the three divisions of the third molar of the true Suidse in great simplicity. 

 There are two bicuspidate lobes corresponding to the two principal lobes of molar 1 and molar 2, 

 and, like them, enclosing a single azygos lobe in the middle line between them. This azygos 

 lobe is developed from the second bicuspidate lobe. There is no ridge developed in Sus anda- 

 manensis on the anterior part of the tooth, i. e. on the face in contact with molar 2. Poste- 

 riorly to two bicuspidate lobes, which already show signs of wear, are seen five smaller cusps, 

 occupying in all a much smaller space than the rest of the tooth. In the males of Sus cristatus 

 these five smaller cusps would, as in well-fed domestic pigs, occupy a very much larger space 

 relatively and absolutely than they do here, or even in Sus scrofa, var. ferus. In Sus barbatus 

 the third lower molars are as simple as they are in Sus andamanensis, and, like this Sus, have the 

 third molars of the upper jaw simpler still than the lower. The five posterior cusps consist of 

 one placed mesially in the interspace between the primary cusps of the second pair, of three 

 placed like the dots in the sign ■ . ■, and of a fifth, not constant, accessory cusp placed on the 

 inner side. The four latter are represented in the upper jaw of this pig by two, and in Sus 

 barbatus by one main cusp. 



