DAKOTA AND NEBRASKA. 



141 



This family, represented in the recent fliuna of the earth hy the Camel and Lama, 

 contained many more representatives in former geological eras. In the fauna under 

 investigation it appears to have heen well represented. The remains viewed as be- 

 longing to it have been referred to six extinct genera, comprising eight species. 



Two of the genera are of the miocene period ; the remains of one — Po^roihermm — 

 having been obtained from bed B of Dr. Hayden's section, in association with remains 

 of Oreodon Calbertsoni, etc. The fossil upon which the genus Protomeryx was founded 

 was obtained from bed D of the same section. The other genera belonged to the 

 pliocene period, — the remains of three species of Procamelus, and those oi Homocamelus, 

 Megalomeryx and Merycodus having been obtained from bed F of Dr. Hayden's 

 section. 



PCEBROTHERIUM. 



The name Poebrotherium is applied to an extinct genus of ruminating animals, 

 apparently most nearly allied to the Camel and Lama among existing animals. 



PCEBROTHERIUM WiLSONI. 



A unique species, to which the above name was given, was established on a speci- 

 men consisting of the facial portion of a skull from the Mauvaises Terres of White 



* The antero-posterior diameter is taken between the most prominent points externally in the case of the 

 upper teeth, internally in the lower teeth. The transverse diameter is taken between the most prominent 

 points anteriorly. 



