On the Geological Age of the White Mountains. A15 
- Generalizing the position and dip of these clearly mechanical 
but altered strata, on both sides of the gorge of the Saco, we — 
think that there are ample data for inferring the existence of a 
great anticlinal fold or axis, crossing the valley in a direction 
nearly N. W. and S. E., as represented by the line wy. This 
axis is plainly indicated on each side of the Gorge by a deep 
depression in the summit line of the mountain, especially in the 
crest which overlooks the valley on the western side. At this 
latter place the situation and bend of the axis line is easily dis- 
cernible, even from the valley below, in consequence of the con- 
trast of certain dark-colored argillaceous strata, in color and bed- 
ding, to the other rocks. 
In the flank of the mountain, capped by the highly altered 
white granitized sandstone already mentioned, we discover on 
the west side of the Gorge, about one third of a mile below the 
Notch and within one hundred feet of the road, a thick bed of a 
light brownish altered shale, imbedded with a nearly vertical dip 
between strata of the metamorphic sandstone before referred to, 
as so nearly granitic in its aspect. This shale is replete with 
fossils of recognizable genera and species, but in the state of casts 
and mere impressions. ‘I'he removal of the substance of the 
fossils from the rock, has probably been the result of filtration 
and solution, completed previously to that mtense heating of the 
strata. by which the more fusible masses were so extensively 
baked and metamorphosed. 
» Among the fossils are what appear to be fish-scales, also a 
small Agnostis, the specimens of which though only impressions, 
have a strong likeness to the Agnostis latus of our Levant series, 
(Clinton group of New York.) We recognize likewise a Cythe- 
rina, like C. alta, of the same formations. There are also innumer- 
able minute objects, which are probably the organs of some small 
crustacean. In addition to these, we recognize among the shells, 
the Atrypa ferruginea, (nobis,) so characteristic of the Levant 
series in Pennsylvania and Virginia, and a small: tumid shell, 
probably also an Atrypa, identical, we think, with another Le- 
vant species. Also a Lingula like L. Clintoni. Some specimens 
abound in very minute globular bodies, somewhat like the gran- 
ules of green sand in color, but which may possibly be organic. 
These and other seemingly organic forms we hope soon to sub- 
ject to a more thorough examination than we have yet been able 
to give them. 
