ILLUSTRATIONS IN THE TEXT 



XXXI 



FIG. PAGE 



342. Sketch maps showing the relationships of drumlins and eskers . . 316 



343. View of a drumlin, showing an opening in the till . . . .317 



344. Outline map of the front of the Green Bay lobe to show the relation- 



ships of drumlins, moraines, outwash plains, and ground moraine 317 



345. Character profiles referable to continental glacier . . . .318 



346. View of the flood plain of the ancient Illinois River near Peoria . 320 



347. Broadly terraced valleys which mark the floods that once issued from 



the continental glacier of North America 321 



348. Border drainage about the retreating ice front south of Lake Erie . 321 



349. The "parallel roads" of Glen Roy in the Scottish Highlands . . 322 



350. Map of Glen Roy and neighboring valleys of the Scottish Highlands . 322 



351. Three successive diagrams to set forth the late glacial lake history of 



the Scottish glens 324 



352. Harvesting time on the fertile floor of the glacial Lake Agassiz . . 325 



353. Map of Lake Agassiz 325 



354. Map showing some of the beaches of Lake Agassiz and its outlet . 326 



355. Narrows of the Warren River where it passed between jaws of granite 



and gneiss ........... 327 



356. Map of the valley of the Warren River near Minneapolis . . . 327 



357. Portion of the Herman beach on the shore of the former Lake Agassiz 328 



358. Map of the continental glacier of North America when it covered the 



entire St. Lawrence basin ........ 329 



359. Outline map of the early Lake Maumee 330 



360. Map to show the first stages of the ice-dammed lakes within the 



St. Lawrence basin 330 



361. Outline map of the later Lake Maumee and its outlet . . . 332 



362. Outline map of lakes Whittlesey and Saginaw ..... 333 



363. Map of the glacial Lake Warren 333 



364. Map of the glacial Lake Algonquin .334 



365. Outline map of the Nipissing Great Lakes 335 



366. Probable preglacial drainage of the upper Ohio region . . . 337 



367. Diagrams to illustrate the episodes in the recent history of a Con- 



necticut river . . 338 



368. The notched rock headland of Boyer Bluff on Lake Michigan . . 341 



369. View of Mackinac Island from the direction of St. Ignace . . .342 



370. The " Sugar Loaf," a stack of Lake Algonquin upon Mackinac Island 342 



371. Beach ridges in series on Mackinac Island ...... 343 



372. Notched stack of the Nipissing Great Lakes at St. Ignace . . . 343 



373. Series of diagrams to illustrate the evolution of ideas concerning the 



uplift of the lake region since the Ice Age . ... . 344 



374. Map of the Great Lakes region to show the isobases and hinge lines of 



uptilt 345 



375. Series of diagrams to indicate the nature of the recovery of the crust 



by uplift when unloaded of an ice mantle . . ... 346 



376. Portion of the Inner Sandusky Bay, for comparison of the shore line 



of 1820 with that of to-day . . . . . . .350 



