424. Effects of differential melting and subsequent refreezing upon a glacier surface 396 425. Dirt cone with its casing in part removed 396 426. Schematic diagram to show the manner of formation of glacier cornices 397 427. Superglacial stream upon the Great Aletsch Glacier 398 428. Ideal form of the surface left on the site of a piedmont glacier apron 399 429. Map of the site of the earlier piedmont glacier of the Upper Rhine 399 430. Diagram and map to bring out the characteristics of newland lakes 402 431. View of the Warner Lakes, Oregon 402 432. Schematic diagram to illustrate the characteristics of basin-range lakes 403 433. Schematic diagram of rift-valley lakes and the valley of the Jordan 403 434. Map of the rift-valley lakes of East Central Africa 404 435. Earthquake lakes formed in 1811 in the flood plain of the Lower Mississippi 404 436. View of a crater lake in Costa Rica 405 437. Diagrams to illustrate the characteristics of crater lakes 406 438. View of Snag Lake, a coulée lake in California 406 439. Diagrams to illustrate the characteristics of morainal lakes 407 440. Diagram to show the manner of formation of pit lakes 408 441. Diagrams to illustrate the characteristics of pit lakes 408 442. Diagram to show the manner of formation of glint lakes 409 443. Map of a series of glint lakes on the boundary of Sweden and Norway 409 444. Map of ice-dam lakes near the Norwegian boundary of Sweden 410 445. Wave-cut terrace of a former ice-dam lake in Sweden 410 446. View of the Márjelen Lake from the summit of the Eggishorn 411 447. Diagrams to illustrate the arrangement and the characters of rock-basin lakes 412 448. Convict Lake, a valley-moraine lake of California 413 449. Lake basins produced by successive slides from the steep walls of a glaciated mountain valley 414 450. Lake Garda, a border lake upon the site of a piedmont apron 414 451. Diagrams to bring out the characteristics of ox-bow lakes 415