Peterson: Miocene Beds of Nebraska and Wyoming. 29 



The vertebral formula of Promerycochcerus carrikeri is : cervicals 

 seven dorsals fourteen, lumbars six, sacrals eight, caudals fourteen (?). 

 The skull is short and deep, the neck short and robust, the neural 

 spines of the dorsals are high, the lumbar vertebne are heavy, with 

 strong zygapophyses and thin transverse processes which are much 

 extended transversely at the distal extremities. There are eight well 

 coossified vertebra in the sacrum. The caudal region was of medium 

 length judging from the four anterior caudals which are at hand. 1 he 

 thoracic cavitv is of large size. The limbs are short and heavy. The 

 broad muzzle, the large feet and the proportions of the skeleton recall 

 the general structural outlines of the hippopotamus. The animal was 

 heavy and no doubt comparatively slow. Its habitat was perhaps on 

 the borders of lakes and rivers. 



Measurements of the Restored Skeleton of 

 Promerycochcerus carrikeri. 



cm. 

 172 



Length of dorsal region ■> 



. _ >o 



Total length of the skeleton, approximately. 



on. 





Length of lumbar regi 



Length of sacrum 



36.5 

 Length of pelvis J 



Transverse diameter of pelvis, anteriorly 3 



Height of skeleton at first dorsal 72 



Phenacoccelus typus 7 gen. et sp. nov. 



Much material of this genus was collected in the upper Monroe 



Creek beds at the head of Squaw Creek, Sioux County, Nebraska. 



The specimen, No. 1263 (Carnegie Museum Catalogue of Vertebrate 



Fossils), which consists of the greater portion of a skeleton, is selected 



as the type. 



Principal Characters. 



Skull rather brachycephalic, merycoidodont in structure and in the 

 pattern of the teeth If, C\, Pf , Mf. There are two elongated and 

 narrow foramina on top of the skull, situated at the anterior part of 

 the frontals, one on either side of the median line, somewhat similar 

 to those in Leptauchenia and Cyclopidius. The cranium is elongated, 

 the facial region short, and there are noticeable antorbital vacuities and 



1 The generic name is given with reference to the vacuities of the skull, which 

 are somewhat similar, but much smaller than in Cyclopidius, from which it is sepa- 

 rated by the possession of three incisors in the upper and lower jaws. 



