862 H. H. GODWIN-AUSTEN ON TERTIARY FORMATIONS 
exposed position, further from the steep slope of the hill behind an , 
against which they were deposited. 
Fig. 5.—Section across the Chiusella at the Ponte dev Preti near 
Strambinello. 
New Bridge 
ge -=— == a tz 
y 36 
== 
pete r 
YASS 
"ees rS -Diorite. Moraine. 
=| Pliocene breccia with débris of diorite. ¢ [surface soil. 
-d=5— 
c Newer Pliocene with shells.. 
In the Museum at Ivrea I was shown a collection of marine shells 
found in the Newer Pliocene beds of this gorge, Pectcn jacobaus being 
common. Not far distant, beyond St. Giovanni, in the Borriana 
ravine, the Pliocene beds are again met with; but only a few feet of 
them are visible in the bed of the ravine. I could find no marine 
shells; and Signor Luigi Bruno, who knows the country and its 
geology well, told me that here they are very rare indeed. At the 
lowest exposed level was a bed of pale bluish sandy loam, which con- 
tained fragments of long pieces of fossil wood a good deal carbonized. 
The great massive moraine-deposits rest upon aud surround this rem- 
nant or outlier of the Phocene formation, which no doubt in a similar 
way underhes the terminal moraine as far as those exposed on and 
near the Lago di Candia. At first the higher beds were destroyed 
by the advancing ice, and were broken up and contorted, portions 
only being finally protected from further denudation by the moraine 
matter being piled up above them. 
When we survey this country from some central and commanding 
point, sueh as the Castigha hill in Ivrea, the position of these Plio- 
cene beds in the east-to-west gorge of the Chiusella is better under- 
stood. ‘They are seen lying close under the steep slope of the diorite 
ridge which extends from Brosso to Vistorio, and which is capped 
by the great right lateral moraine of the old Dora Baltea glacier ; 
this, when entire, swept over the gorge, then filled with ice, and 
was united in one continuous moraine with that on the south at 
Bairo &c. The ice and these accumulations moving at right angles 
to the narrow gorge, its force was considerably diminished just 
under the lee of the diorite face of the hill above Strambinello, and 
