EVIDEKCE THAT BEDS ARE AFTOKIAN 135 



17. Cox 'pit}^ — This is located in the southeast bluffs of the Boyer 

 River, in the northeast quarter of section 24, township 78 north, range 

 xliv west, and is one of the finest sections of the entire series. The 

 Aftonian here rises to a height of about 35 feet above the Boyer bottoms. 



The section shows the following: 



4. Loess, capping the ridge above, but not appearing in the pit. 

 3. Loveland, exposed just above the pit. 



2, Kansan, typical bluish calcareous till, 13 feet. 

 1. Aftonian : 



Sand, varying in coarseness, beautifully cross-bedded, 21 feet. 



Gravel, light colored, cross-bedded, with small boulders, 6 to 8 

 feet. 



Gravel, dark colored with much MnOo, 6 to 8 feet. 



Fine bluish silt, 6 inches. 



White sand, penetrated to a depth of 4 feet. 



The xlftonian is typical in structure and composition, and both gravel 

 beds contained mammalian and molluscan fossils. No fossils were ob- 

 served in the sand. 



The line between the Aftonian and Kansan is very sharply defined, 

 more or less ferruginous, and with large nodular calcareous plates. Afto- 

 nian sand and gravel "boulders,*' which are scattered through the lower 

 part of the Kansan, also give evidence of plowing by the latter. 



The following mammalian fossils were collected: 



1. Elephas imperator, lower jaw (see ibid., plate 25, figure 1). 

 16. Elephas colum'bi, molar. 



12. Mammut americanum, sixth molar (see ibid., figure to left of fig- 

 ure 6, plate 25). 

 Mammut americanum, other molars. 

 42 (a). Mammut americanum, piece of tusk (see ibid., figure just 

 below left end of figure 4, plate 25). 



5. Elephas or Mammut, right tibia (see ibid., plate 25, figure 5). 



18, 25. Elephas or Mammut, caudal vertebrae. 

 30. Elephas or Mammut, pubic bone, part. 



138. Elephas or Mammut, distal end of radius. 



45,46. Elephas or Mammut, scapula, fragments (see ibid., plate 25, 

 figure 9). 



19. Vertebra, unidentified. 

 57. Incisor, unidentified. 



64. Bos , horn cores (see ibid., plate 23, figure 1). 



83. Astragalus of large ruminant (see ibid., plate 22, figure 1). 



Piece of cannon bone of large ruminant (see ibid., plate 22, fig- 

 ure 3). 

 183. Camelus (?), second right inferior molar. 



IS See ibid., plate 2, plate 16, figure 1, and plate .33, figures 1 and 2. 



