Geology of the Valley of Reposoir in Savoy. 115 
at the inn); I estimate its peak at about 2300 metres. It 
divides the valley of Reposoir into two parts, which unite at 
the north-east and south-west extremities of the valley. The 
Montagne des Anes is connected with the chain of the Vergys 
to the north by the Col de la Touviére or des Ferrands, and 
on the south to the chain of Pointe-Percée by the Col des 
Anes. These two cols are very interesting in respect to 
their geology. 
It is therefore evident, that the Montagne des Anes rests 
wholly on the beds which form the chain of the Vergys and 
Pointe-Percée, or, what is the same thing, these beds run be- 
neath this mountain. Such is the position and structure of 
this valley. I now proceed to the geological part of this 
notice. 
The two chains of mountains just spoken of are composed of 
neocomian beds ; the greatest mass belongs to the limestone 
of the first zone of rudistes or limestone with Chama Ammonia. 
In some of its most elevated parts we perceive the inferior 
neocomian, which has pierced through the upper stage of the 
neocomian. It is characterised by the Toxaséer complana- 
tus, Ag., which is found in great abundance in the Col du 
Balafras (2303 metres, barometric observations, chain of the 
Vergys), and at the Cheminée du Meiry (chain of Pointe- 
Percée.) The jurassic formation is seen below the neocomian 
formation on the southern reverse of this latter chain; while 
it cannot be seen in the chain of the Vergys. 
The neocomian formation of which we have spoken is 
covered to a great thickness with white limestone, with 
Chama Ammonia, on which lies green sandstone, or the 
albian formation in beds, or in portions of beds, lying here and 
there on thesurface. This formation is rich in fossils on the 
southern reverse of the chain of the Vergys, on the stairs of 
Sommiers, and at Roselletaz, in the chain of Pointe-Percée. 
According to the observations which Murchison commu- 
nicated to the meeting of the Helvetie Society of Natural 
Sciences, met last year at Soleure, this formation ought to 
he covered in some localities by a limestone which appears 
to be equivalent to the limestones of Seewen and the white 
chalk. This rock is covered by a blackish calcareous sand- 
