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 exeelsus, Leidy, . ; " * | 56. Felis (Pseudalurus) intrepidus, Leidy, * 
41. Equus (Protohippus) awrishas Leidy, ; ; * | 57. Alurodon ferox, Leidy, * 
58. Canis sevus, Leidy, * 
epricaiic is 59. Canis temerarius, Leidy, * 
42. Steneofiber Nebrascensts, Leidy, . ‘ F * * 00, Conse wafic, Laide, e 
nr mays Syphs, kane, 7 : : ‘ eas 61. Canis (Epicyon) pdt Leiay, * 
44, Palaolagus Haydent, Leidy, i F : * * 
45. Eumys elegans, Leidy, : : Pr, CHEIONI ie 
46. Hystrix (Hystricops) venustus, Leidy, wo Oe ee Nebrascensis, Leidy : . RK 
47. Castor (Eucastor) tortus, Leidy, . * | 63. Testudo (Stylemys) Nidircloviase Leidy, : * 
CARNIVORA. MOLLUSCA. 
48. Hyenodon horridus, Leidy, . * 64. Helix Leidyi, Halland Meek, . * 
49. Hyenodon eruentus, Leidy, . * 65. Planorbis Nebrascensis, Evans and PRE, * 
50. Hyenodon crucians, Leidy, . . 66. Lymnea diaphana, Evans and Shumard, * 
51. Amphicyon vetus, Leidy, “J 67. Lymnea Nebraseensis, Evans and Shumard, . * 
52. Amphicyon gracilis, Leidy, “a 68. Physa secalina, Evans and Shumard, * 
53. Leptarctus primus, Leidy, ‘ = * 
54. Deinictis felina, Leidy, 2 : gh ae CRUSTACEA. 
55, Machatrodus primevus, Leidy, . 5 rw 69. Cypris Letdyi, Evans and Shumard, . . 3 
CHAPTER Att 
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 a paces 
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 
