The largest glacier known to discharge wholly in the Yukon basin is one which lies approximately on the 141st meridian, called the, Klutlan from the native name of the river to which it gives rise. Its source is in the great snow fields between mount St Elias and the high peak on the northern border of the range called Nat-azh-at by the natives. It extends several miles beyond the foot of the range, though it is rapidly receding at the present time, and is between four and five miles broad where it enters the valley. The stagnant ice at the front of the retreating glacier is buried under a great accumulation of moraine material continuous with the terminal moraine, so that it is impossible to determine the exact limits of the ice. The heavy mantle of vegetation which covers the terminal moraine continues a mile or more beyond the outer edge of the ice, becoming gradually less abundant as the active portion. of the glacier is approached. The moraine in front of the Klutlan is the largest accumulated by any of the interior glaciers. It is composed very largely of the white volcanic tufa already described, but with this are mingled many angular fragments of ainygdaloid lavas and a few of granite and gneiss. Much of the moraine has been removed by streams flowing from the glacier, but remnants 200 feet or more in thickness extend nearly across to the high land north of the valley. The second of the White river glaciers is about midway between the Klutlan and Scolai pass. It is much smaller than the Klutlan and does not push out into the valley, but its front forms a wall of ice something over a mile in length from side to side of the narrow valley in which it lies.