Restoration of Aceratheriiim fossiger Cope. 



BY S. \V. WILLISTON. 



(With Plate VIII.) 



As is well known, the larger part of western Kansas is overlaid by 

 a freshwater deposit lying unconformably upon the Cretaceous. This 

 deposit had been traced as far east as Wichita, and, by Professor 

 Hay, in isolated patches to Junction City. As has been shown by 

 both Professor Hay and myself, the topography of the western part 

 of the state had become essentially that of the present day before its 

 deposition. Its c ief characteristic is a bed of coarse sandstone, 

 often filled with large, water-worn pebbles, whose origin was of course 

 the Rocky Mountains. This stone, however, varies greatly in differ- 

 ent places; sometimes composed largely of lime, and even furnishing 

 a serviceable limestone for building purposes; in other places it is 

 more sandy or may be a loose sand. The "natural lime," a pulveru- 

 lent carbonate of lime, with some sand, used in various places for 

 building, is from the same deposit. In general, howe/er, the deposit 

 is best characterized by the name commonly given to it of "mortar 

 beds." These " mortar beds " are everywhere found underlying the 

 extensive tablelands of the plains, a fact easily demonstrable by the 

 wells, which, almost invariably penetrate to the lowermost parts over- 

 lying the impervious shales of the Cretaceous, at a depth, on the level 

 plains of from one hundred to one hundred and twenty-five feet. 



The lower portion of the deposit is the Loup Fork Tertiary; the 

 upper the Pliocene, but just how much belongs to each is at present 

 uncertain. A recent find of characteristic Pliocene mammals about 

 one hundred feet above the chalk in Sherman county leaves no ques- 

 tion of the age of the uppermost deposits. In the coarser and harder 

 sandstone of the Loup Fork beds, the prevailing vertebrates are the 

 larger Testudos; in the looser sand, either of the same age or a little 

 older, occur most frequently the various mammalian remains which 

 have been discovered in such abundance and in widely remote locali- 

 ties. Of these remains those met with by far the most frequently 

 pertain to two or more species of Rhinoceros, which have been found 

 in different localities from the extreme south to the extreme north of 

 the state as well as in Nebraska. Of these, Aceratheriicm fossiger is 

 the only one commonly met with. 



(•.289) liAN. UNIV. QUAB. VOL. U, NO. -1, APB. 1894, 



