OF THE UPPER MISSOURI. 107 
Beds in ascending order. | Beds in ascending order. 
A.B. C.D.E.F. A. B.C. D.E.F. 
40. Equus excelsus, Leidy, - 3 ‘ 5 5 * | 56. Felis (Pseudalurus) intrepidus, Leidy, 5 * 
41. Equus (Protohippus) perditus, Leidy, . : x | 57. Alurodon ferox, Leidy, % 
RODENT! | 58. Canis sevus, Leidy, * 
is . . . 
42. Steneofiber Nebrascensis, Leidy, . . * * see Mee aT: _ 
) 2 “ 60. Canis vafer, Leidy, ° * 
> Usa lQiiCaegS Lappe TANT, | , : 5 ia 61. Canis (Epicyon) Haydent, Leidy, * 
44. Palaolagus Haydeni, Leidy, : : e * | . 
45. Eumys elegans, Leidy, 5 5 : 0 * j CHELONIA. 
46. Hystrix (Hystricops) venustus, Leidy, 2 * | 62. Testudo Nebrascensis, Leidy, : c . EX 
47. Castor (Eucastor) tortus, Leidy, - : . * | 63. Testudo (Stylemys) Niobrahensis, Leidy, . * 
CARNIVORA. MOLLUSCA. 
48. Hyenodon horridus, Leidy, . 0 i 5 ae 64. Helix Leidyi, Hall and Meek, : ‘ | % 
49. Hycnodon erwentus, Leidy, « s | 65. Planorbis Nebrascensis, Evans and Shumard, 
50. Hyenodon crucians, Leidy, - a | 66. Lymnea diaphana, Evansand Shumard, * 
51. Amphicyon vetus, Leidy, - | 67. Lymnea Nebrascensis, Evans and Shumard, . * 
52. Amphicyon gracilis, Leidy, . * | 68. Physa secalina, Eyans and Shumard, . 5 * 
53. Leptarctus primus, Leidy, . 9 0 * 
54. Detnictis felina, Leidy, : : > es CRUSTACEA. 
55. Machatrodus primevius, Leidy, . 5 ae 35 | 69. Cypris Letdyi, Evans and Shumard, . 0 * 
CHAPTER XII. 
QUATERNARY DEPOSITs. 
Although the various superficial deposits which I include under the above caption are 
very fully developed in the Northwest, and exert a great influence on the external features 
of the country, I shall be able, in this connection, to speak of them only in a brief and 
general way. I propose, however, to treat the subject more thoroughly in a future official 
report, now in course of preparation. This division, which has been called surface geology, 
is by no means greatly inferior in importance or interest to the others before treated, and 
no country affords more suitable or more abundant material for a memoir on that sub- 
ject than the Northwest. The extensive area covered by deposits of sand, gravel, water- 
worn boulders, and erratic blocks, the examples of the denuding and eroding power of 
water, which have given such unique features to much of the scenery, the river terraces, 
and yellow marl or bluff formation,—all these subjects will, when thoroughly studied, add 
very greatly to the interest felt in this department of geological research. 
In Prof. Swallow’s Geological Report of the State of Missouri, the Quaternary deposits 
as they occur along the Missouri river, from its mouth to Council bluffs, are quite fully 
discussed, and inasmuch as they are of a similar character where they are observed from 
