10 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
Galena gulch are too slender in comparison with the trough floors 
between them; and it was strongly our impression that the contours 
were drawn too directly across the trough floors, making them flat- 
floored instead of round-floored. One reason for these imperfections 
was doubtless the haste with which the field work for these earlier 
maps was done, as the result of pressure for square miles rather than 
for accuracy of results; another reason may have been the habit 
acquired in non-glaciated mountains, of drawing spurs and valleys 
with normal forms instead of with the specialized features of glacial 
forms. Still a third reason must have been the want of sufficient 
inspection in the field, in the absence of which many errors clearly 
visible on the scale of publication were given the authority that 
their appearance on official maps naturally carries. A map drawn 
with some appreciation of the differences between normal and glacial 
forms would, I believe, be significantly unlike the Leadville sheet. 
The Colorado Midland railroad tunnels through the northern 
part of the Sawatch range under Hagerman pass, next north of Mt. 
Massive. The ascent to the tunnel, after one crosses the Arkansas 
river west of Leadville, is full of scenic interest, more especially 
when the scenery is interpreted in view of its glacial origin.’ The 
ride must have been more remarkable a few years ago than now; 
for the railroad originally had a shorter tunnel at a height of about 
11,800 feet; now it has a longer tunnel, about two miles in length, 
at an altitude of 11,000 feet; thus saving a heavy climb for the trains 
and two hours, we were told, of time, but depriving the traveller 
of the sight of the upper cirques that was formerly offered. Yet 
even the present route is an unusual one. It turns west from the Ar- 
kansas valley and enters a morainic amphitheater through a stream- 
cut notch; it then ascends the spur-less, ravine-less southern side 
of the glacial trough to the trough-head, in the neighborhood of 
which the tunnel begins. During the ascent, one sees to great ad- 
vantage the trough floor, of which the lower part is occupied by an 
artificial reservoir, and the middle part by a green meadow through 
which a stream wanders in a somewhat braided course. For a while 
the road follows the inner slope of the southern lateral moraine; 
then the southern rock wall of the trough. The trough forks near 
its mid-length; two branch glaciers that here joined must have been 
of about equal size, as neither branch trough hangs over the floor of 
the other. The simplicity of the form of the trough wall is evidently 
an advantage in the laying of the railroad; for the wall offers 
neither spurs to turn around nor side ravines to bridge across. In 
