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In the vicinity of Mt. Aigoual, in the central portion of the Cevennes, a limited outcrop of ancient glacial tillite has been discovered. The scarcity of the glacial phenomena, which are usually so abundant in regions of Pleistocene glaciation, and the entire absence of the topographic situations, where alpine glaciers could have formed, indicate that the tillite in question is considerably older than Pleistocene. The peculiar location of the glacial evidence in certain mature valleys, which physiographic investigation shows to be of mid-Tertiary age, has led to the conclusion that the glaciation occurred before the close of Miocene time.

Recently discovered evidence that several glaciers once existed within thirty miles of the site of the business center of Los Angeles is set forth in this paper. The size of the glaciers, the moraines, the amount of ice erosion, a glacial lake-basin, the age of the glaciation, and the factors favorable to the glaciation are all discussed.

Submarine valleys may be classified into three groups. One group resembles youthful river valleys, another fault grabens, and a third glacial troughs. There are many reasons for believing that the valleys of this last group have been shaped by glacial excavation. They are found exclusively off glaciated coasts. They contain the deep-rimmed depressions, trough-shape, and relatively straight walls characteristic of glacially excavated valleys. Evidence of the presence of moraines within these shelf-troughs has been discovered. Finally the continental shelves off glaciated coasts are much deeper on the average than those off unglaciated areas.

Most glacial studies have been chiefly concerned with motion, advance and recession, transportation by the ice, and the carving of land forms. The smaller features, discussed in this paper, have generally not been described. Many of these lesser features, located on and near the terminal parts of valley glaciers, are here named and described for the first time.

The Yellowstone Valley, between the Gallatin and Beartooth ranges in southern Montana, is the easternmost of the Tertiary basins characteristic of the Northern Rockies. It is a structural basin bordered by a fault along its eastern margin and is partially filled by Upper Miocene-Lower Pliocene beds. Erosion surfaces in adjoining mountains and along the valley are described and correlated. Obscure phases of the Tertiary and early Quaternary history are pointed out. Two substages of the Wisconsin glaciation are considered, and the possibility of pre-Wisconsin glaciation is recognized.

Sunlight Creek flows northeastward into Clarks Fork River in the northern Absaroka Mountains of northwest Wyoming. Two periods of glaciation are here recognized from the degree of erosion of the moraines. An early ice sheet from the Beartooth Plateau to the north invaded Clarks Fork Valley; but, being unable to move eastward through the Clarks Fork Canyon to the plains as rapidly as ice filled the valley, it moved south against the Absaroka Range, filling the lower ends of valleys in that range and even overflowing the lower passes in the Clarks Fork-Sunlight divide. This ice and its moraine dammed the Sunlight Valley and formed a lake, the aggradation of which has floored the Sunlight basin. The later glaciation was of the normal valley type with a glacier extending part way down Sunlight Creek Valley. A few small glaciers still exist today.

Within each of the major valleys east of the Continental Divide in Rocky Mountain National Park, Colorado, similar associations of glacial land forms are repeated. The character and pattern of distribution of moraines, terrace remnants of valley trains, and ice-eroded upper-valley forms are presented as evidence that glaciers occupied these valleys during at least three stages. All observed glacial land forms lie within well-developed valleys, and no evidence was found that glaciers had extended as far east as Estes Park. Nor was any evidence found of a very early and extensive glaciation corresponding to the Prairie Divide² and Tungsten Mountain (pre-Wisconsin) tills recognized on the high in-tervalley divides just north and south of Rocky Mountain National Park.

The recent papers of Professor Sardeson' and Mr. Campbell2 on folds in surface strata, the former within and the latter without the glaciated region, suggest the publishing of some analogous observations made in Owasco Lake (New York) valley. Two questions will be considered in this paper: (i) Did overriding ice produce the folds, and, (2) if so, what bearing does this disturbance of subjacent strata have in the question of glacial erosion ? The localities concerned are shown in Fig. i, which is a transfer of a portion of the Moravia Quadrangle, omitting the 20-foot contour intervals. Owasco Lake lacks one-fourth of a mile of reaching the northern margin of this sheet. Its former higher levels extended several miles southward, as described in the papers of Watson3 and Fairchild,4 these higher levels being marked by numerous deltas. Southward from Locke the valley branches about a salient which reaches an altitude of 1,500 feet. The inlet stream rises some thirteen miles south of the present lake in an outwash plain near Freeville. The rock topography suggests a former divide between Locke and Groton.