214 UNGULATA order vii 



fossa weak. Parietal bones almost entirely removed to the occipital surface. 

 Excessive development of air-cavities in all bones of the cranium. Horns 

 far back, short, spiral and keeled. Teeth subbrachyodont. Lower Pliocene ; 

 Samos, Bessarabia, and Maragha. C. argalioides Forsyth Major. 



Group 4. HipPOTRAGiNAE Gray. 



Skull long, cranial axis hent. Ethmoidal 'vacuity present ; lachrymal fossa absent. 

 Horns over the orbits curved or straight, always of considerable length, and roundish 

 in cross-section. Teeth hypsodont, with strong basal pillars; in the older forms 

 brachyodont, with only weak basal pillars. 



Hippotragus Sundevall. Horns strongly recurved. Teeth hypsodont, with 

 strong basal pillar. Pliocene ; India. H. palaeindicus Lydekker. Pleis- 

 tocene ; Algiers. Eecent ; Africa. 



Oryx Blainville. Horns long, straight, inclined backward. Teeth with 

 moderate basal pillars. Recent ; Africa. 



Palaeoryx Gaudiy. Horns moderately long, roundish in cross -section, 

 only slightly inclined backward. Teeth brachyodont, with weak basal pillars. 

 Lower Pliocene ; Pikermi and Maragha. P. pallasi Wagner. Samos. P. 

 majori and P. stutzeli Schlosser. The former of these species occurs also at 

 Odessa. Middle Pliocene ; P. meneghinii Riitimeyer, P. boodon and P. cordieri 

 Gervais. 



Tragoreas Schlosser. Horns strongly inclined backward. Lower Pliocene ; 

 Samos. T. oryxoides Schlosser. 



Addax Rafinesque. Horns long and lyrate, spirally curved. Teeth with 

 moderate basal pillars ; superior molars with islands of enamel. Recent ; 

 Africa. 



Plesiaddax Schlosser. Teeth slightly hypsodont, similar to those of 

 Addax. Lower Pliocene ; China. 



Group 5. Cervicaprinae Gray. 



Skull moderately long, slightly arched, with ethmoidal vacuity, without lachrymal 

 fossa. Horns rather short, slightly inclined, lyre-shaped. Teeth hypsodont, bovine. 



Of the three genera included here, Pelea Gray, Cobus A. Smith and Cervi- 

 capra Blainville, the last two are indicated by remains in the Pleistocene of 

 Algiers. Lydekker has described two doubtful species of Cobus from the 

 Siwalik Pliocene. 



Group 6. Tragelaphinae Jerdon. 



SkuU long, slightly arched, with ethmoidal vacuity, in the fossil forms with 

 lachrymal fossa also. Horns long, lyre-shaped, keeled, and spired, roundish in cross- 

 section. Teeth always brachyodont, only in fossil forms with weak basal pillar. 



Tragelaphus Blainville; Strepsiceros Hamilton - Smith ; Taurotragus Scl&tev ; 

 Oreas Desmarest. Recent in Africa. One species each of Strepsiceros and 

 Oreas (S. falconeri Lydekker and 0. latidens Lydekker) in the Pliocene of 

 the Siwalik Hills, India. Strepsiceroid teeth occur in the Lower Pliocene of 

 China. Strepsiceros kudu, fossil in the Pleistocene of Algiers. 



