1836.] a new Fossil Genus of the Sivdlik range. 



the Pachydermata, and at the same time so marked by individual pecu- 

 liarities as to be without an analogue in its order. ... 



The fossil remain of the Sivatherium, from which our description is 

 taken, is a remarkably perfect head. When discovered, it was fortunately 

 so completely enveloped by a mass of stone, that although it had long been 

 exposed to be acted upon as a boulder in a water-course, all the more 

 important parts of structure had been preserved. The block might have 

 been passed over, but for an edging of the teeth in relief from it, which 

 gave promise of something additional concealed. After much labour, the 

 hard crystalline covering of stone was so successfully removed, that the 

 huge head now stands out with a couple of horns between the orbits, broken 

 only near their tips, and the nasal bones projected in a free arch, high 

 above the chaffron. All the molars on both sides of the jaw are present 

 and singularly perfect. The only mutilation is at the vertex of the 

 cranium, where the plane of the occipital meets that of the brow: and 

 at the muzzle, which is truncated a little way in front of the first molar. 

 The only parts which are still concealed, are a portion of the occipital, 

 the zygomatic fossae on both sides, and the base of the cranium over the 

 sphcenoid bone. 



The form of the head is so singular and grotesque, that the first glance 

 at it strikes one with surprise. The prominent features are — 1st, the great 

 size, approaching that of the elephant : 2d, the immense developement and 

 width of the cranium behind the orbits: 3d, the two divergent osseous 

 cores for horns starting out from the brow between the orbits: 4th, the 

 form and direction of the nasal bones, rising with great prominence out of 

 the chaffron, and overhanging the external nostrils in a pointed arch : 

 5th, the great massiveness, width and shortness of the face forward from 

 the orbits : 6th, the great angle at which the grinding plane of the 

 molars deviates upwards from that of the base of the skull. 



Viewed in lateral profile, the form and direction of the horns, and the 

 rise and sweep in the bones of the nose, give a character to the head 

 widely differing from that of any other animal. The nose looks something 

 like that of the rhinoceros ; but the resemblance is deceptive, and only 

 owing to the muzzle being truncated. Seen from in front, the head is some- 

 what wedge-shaped, the greatest width being at the vertex and thence 

 gradually compressed towards the muzzle ; with contraction only at two 

 points behind the orbits and under the molars. The zygomatic arches are 

 almost concealed, and nowise prominent : the brow is broad, and flat, and 

 swelling laterally into two convexities; the orbits are wide apart, and 

 have the appearance of being thrown far forward, from the great produc- 

 tion of the frontal upwards. There are no crest or ridges : the surface of 

 the cranium is smooth, the lines are in curves, with no angularity. 

 From the vertex to the root of the nose, the plane of the brow is in a 

 straight line, with a slight rise between the horns. The accompanying 

 drawings will at once give a better idea of the form than any description. 



Now in detail of individual parts ; and to commence with the most 

 important and characteristic, the teeth : 



There are six molars on either side of the upper jaw. The third of the 

 series, or last milk molar, has given place to the corresponding permanent 

 tooth, the detrition of which and of the last molar is well advanced, and 

 indicates the animal to have been more than adult. 



The teeth are in every respect those of a ruminant, with some slight 

 individual peculiarities. 



The three posterior or double molars are composed of two portions or 

 semi-cylinders, each of which incloses, when pai-tially worn down, a double 

 crescent of enamel, the convexity of which is turned inwards. The last 

 molar, as is normal in ruminants, has no additional complication, like that 



