Map showing glaciated areas in North America and Europe 130 41. Maps showing lines of _débris_ extending from the Alps into the plains of the Po 134 42. Section of the Cefn Cave 148 43. Map showing moraine between Speeton and Flamborough 156 44. Diagram-section near Cromer 166 45. Section through the westerly chalk bluff at Trimingham, Norfolk 162 46. Section across Wales 172 47. Section of cliff at Flamborough Head 176 48. Enlarged section of the shelly sand and surrounding clay at _B_ in preceding figure 177 49. Map showing the glaciated area of Europe 184 50. Map showing old channel and mouth of the Hudson 195 51. New York Harbor in preglacial times 197 52. Section across the valley of the Cuyahoga River 200 53. Map of Mississippi River from Fort Snelling to Minneapolis 209 54. Map showing the effect of the glacial dam at Cincinnati 213 55. Map of Lake Erie-Ontario 219 56. Map of Cuyahoga Lake 221 57. Section of the lake ridges near Sandusky, Ohio 223 58. Map showing stages of recession of the ice in Minnesota 225 59. Glacial terrace on Raccoon Creek, in Ohio 227 60. Ideal section across a river-bed in drift region 229 61. Map of Lakes Bonneville and Lahontan 234 62. Parallel roads of Glen Roy 239 63. Map showing glacial terraces on the Delaware and Schuylkill Rivers 243 64. Palæolith found by Abbott in New Jersey 244 65. Section across the Delaware River at Trenton, N. J. 245 66. Section of the Trenton gravel 246 67. Face view of argillite implement found by Dr. C. C. Abbott in 1876. 247 68. Argillite implement found by Dr. C. C. Abbott, March, 1879 248 69. Chipped pebble of black chert found by Dr. C. L. Metz, October, 1885 249 70. Map showing glaciated area in Ohio 250 71. Palæoliths from Newcomerstown and Amiens (face view) 252 72. Edge view of the preceding 253 73. Section across the Mississippi Valley at Little Falls, Minn. 254 74. Quartz implement found by Miss F. E. Babbitt, 1878, at Little