STUDIES OF THE CYCLE OF GLACIATION 371 
does the fretted upland as exemplified by the Alps. The most 
striking peculiarities of this type are found in the unusual number 
of isolated sharp peaks of monumented aspect (Figs. 4 and 5), 
and this is combined with a general absence of the comb ridge 
(a rare example is shown in Fig. 6) and a frequency of unusually 
low cols or passes (Fig. 7). Unlike the true horns of the Matterhorn 
type, which in the fretted upland are relatively few in number and 
may perhaps represent by their summits points near the original 
surface of the upland, the monuments of the northern Rocky 
Mountains show a tendency to appear in pairs, and in many 
Fic. 1.—View of Mt. Mathews, Bighorn Range, taken from the southeast and 
showing the character of the preglacial surface. At the left in middle distance is a 
cirque. 
instances at least they are remnants of lower portions of the 
preglacial surface (Figs. 5, 8). 
Both in the Bighorn Range and in the Glacier National Park 
the glaciers have today nearly or quite disappeared, being now 
represented by small horseshoe or cliff glacierets only. The 
earlier conditions of nourishment were, however, as we know from 
more or less extended studies, notably different from those of today. 
In the Bighorn Range the glaciers of Pleistocene time extended 
far down the valleys, where strong terminal moraines are found to 
mark the limits of their advance." 
tR. G. Salisbury, ‘‘Cloud Peak—-Sheridan Folio,” U.S. Geol. Swurvey; also, 
N. H. Darton, U.S. Geol. Survey, Prof. Paper 51, pp. 71-91, Pls. 37-36. 
