446 Dr. J. Murie — On the Swatherium giganteum. 



one, and presented many variations whicli would stop the gaps now 

 existing between it and otlier ruminants. The giraffe is but a 

 modified deer; yet withal it differs from the latter tribe very 

 materially. It is tricorned, and the horns are persistent, etc. The 

 length of its fore and hind limbs, and even of such of the fossil 

 species that are known, are disproportionate to each other, the 

 former far exceeding those of all other ruminants. In the teeth 

 alone does the Sivatherium incline to the Giraffidce. 



Coming to the Bovidce, as has been demonstrated, the Sivatherium 

 af&nes itself to oxen in the stoutness of its limbs, sternum, and ver- 

 tebrae, and also in some parts of the skull structure. It is further 

 removed from the goats and sheep, albeit some Ovidce have four horns. 



In the fact of all antelopes having persistent horns, and from other 

 points of skeletal structure heretofore mentioned, the Sivatherium in 

 strictness cannot belong to that group. Yet, as I have enunciated, the 

 strange Saiga, which wavers between sheep and antelopes, possesses 

 several facial features strikingly brought out in relief in the remains of 

 the extraordinary Sivatherium. But thus far likeness ceases, and the 

 Sivatherium, with its deciduous hollow horns, clings most strongly to 

 the imique Prongbuck (Antilocapridce) . This latter animal, not- 

 withstanding its singleness of structural organization, exhibits deer- 

 like proclivities in several points, and notably in the existence of 

 ant-orbital fissures. 



The fossil Bramatherium and Megacerops link themselves with 

 Sivatherium in greatness of dimensions, in being quadricavicorned, 

 and in similitude of dentition ; though these attributes must be used 

 with caution, from the paucity of the fossil remains. 



The Sivatherium, through the Saiga, as I have mentioned, veers 

 towards pachyderms in nasal conformation, and the splitting of the 

 lower limb bones adds to Perissodactyle character. 



To not one of the families spoken of does the Sivatherium con- 

 sistently belong. According as we accept horns, skull, teeth, or 

 bodily framework, so does the Sivatherium ally itself to the different 

 ruminant families. The strongest expression of character weighs 

 towards Antilocapridcs. Admitting as naturalists do that the horns 

 are a guiding wand of taxonomic value, the Sivatherium, though not 

 agreeing in all respects, must truly be classed under the family 

 AntilocapridcB. But I go further than this, and look upon the Siva- 

 therium as a type of a group, and which may be termed the Siva- 

 theridce. Eadiating from it can be traced differentiation of structure 

 allying it to the Bramatherium and Megacerops. Diversely, links lead 

 through the Prongbuck towards the deer, giraffe, and camel ; on the 

 other hand, configurations point undoubtedly to the Saiga, and again 

 its affinities are, as it were, split into lines directed towards the ante- 

 lopes, goats, sheep, and oxen, and even foreshadowing pachydermate 

 conformation. The accompanying diagram illustrates such views, and 

 shows at a glance by what varied tracts we can trace paths from the 

 Sivatherium winding and connecting it with nearly all the ruminants 

 besides the thick-skinned Perissodactyla and Proboscidea. 



By such chains of consanguinity are the observations of the 



