DESCRIPTION OF PLATES. 



509 



Figs. 3, 3 a, and 3 i. — Sus giganteits. Cranium. Upper, palatal, and 

 lateral views. The right zygoma is imperfect, and the left is almost 

 absent ; but, in other respects, the cranium is more perfect than in figs. 

 1 or 2. There are three molars and three premolars on either side. 

 The incisive alveoli and the tuberosity and alveolus of the right 

 canine are also present. — B.M. 



Length of fragment, 14'3in. Width of cranium superiorly at sub-orbital fora- 

 men, rsin. Height of ditto from palate, 3-3 in. Length of canine tuberosity, 

 4' in. Length of molar series, 0'6 in. Length of three true molars, 3-5 in. From 

 posterior border of palate to anterior margin of incisive alveolu.s, 7'6 in. From 

 posterior border of palate to posterior angle of incisive foramen, 8'7 in. Diastema 

 between canine and external incisor, I'in. Width of palate posteriorly, r2 in. 

 Ditto between canines, 2- in. Greatest width of alveoli, r2 in. 



Fig. 4. — Sus giganteus. Lower jaw, right side. The ascending 

 ramus is mostly absent. Shows three molars and three premolars, with 

 canine and incisive alveoli. 



Length of fragment, 11-5 in. Height of horizontal ramus, 2' in. Thickness of 

 ditto, 1-7 in. Length of symphysis superiorly, 3-3 in. Leiigth of three true molars, 

 3"5 in. Length of ditto, with three posterior premolars, 5' in. Interval between 

 first and second premolars, "9 in. Interval between second premolar and canine, 

 1-6 in. Between canine tuberosities, 3-9 in. Width between molars posteriorly, 

 l'5in. Between ditto anteriorly, V7 in. 



Figs. 5 and 5 a. — Sus scrofa (var. Tndicus). 

 lower jaw, not fossil. Upper and lateral views, 

 natiu-al size. — B.M. 



Plate LXX. 



Figs. 1 and 1 a. — Sus (Hippoliyus) Sivalensis (Falc. and Caut.).' 

 Cranium. Upper and palatal views. Except that the zygomatic arches 

 are absent, the specimen is very perfect. Shows three molars and two 

 last premolars on either side, with alveoli of canines and six incisors. 

 The sub-orbitary and incisive foramina are well marked. — B.M. 



Extreme length of fragment, 9-2 in. From post, plane of occipital condyles to 

 anterior margin of incisive alveolus, 9' in. From lower border of occipital foramen 

 to post, border of palate, 2-3 in. From post, border of palate to posterior border of 

 incisive foramen, 5-4 in. Width of palate between second molars, 1-1 in. Width of 

 ditto between inner margins of canine alveoli, 1-05 in. Width of ditto between 

 anterior angles of middle incisive alveoli, '7 in. Greatest width of alveoli, -Sin. 

 Length of the molar series, 4-3 in. Length of the three true molars, 27 in. Dias- 



Entire skull, with 

 One-third of the 



» ' In this extinct genus of quadrupeds 

 from the Himalayan tertiary deposits, 



3 3 



the dental formula shows incisors — -, 



o — o 



and corresponds with that of the Chcero- 

 jpotamus in the number of canines, pre- 

 molars and molars ; but the true molars 

 have a more complex crown, approaching 

 nearer to those of the typical Suidts in 

 the depth and number of the secondary 

 enamel folds. Each upper true molar 

 has its crown cleft by the common or 

 primary crucial valleys, the transverse 

 one passing somewhat obliquely from 

 within forwards and outwards. Each of 

 the four principal lobes is subdivided, 

 not by a vertical central depression, 



but by a fold penetrating its anterior 

 and posterior margins. The enamel at 

 first shows additional minor plications, 

 but is worn down to the simpler pattern 

 above described ; the outer lobes are 

 convex externally. The first premolar 

 is very small and simple, separated by 

 an interval of its own breadth from the 

 second ; both this and the third have 

 transversely compressed crowns ; the 

 fourth has a sub-trihedral crown. The 

 Hippohyus equalled in size the Cheero- 

 potamus, but exhibits as strong a ten- 

 dency towards the Hippopotamoid family 

 as that does towards the plantigrade 

 Carnivora.' — Owen's 'Odontography,' vol. 

 i. p. 562. 



