GEOLOGY OF NEW HAMPSHIRE 59 
boundary of New Hampshire and Maine. Associated with these 
older rocks are slates, sandstones and conglomerates believed to 
be Lower Cambrian. The continuations of the Calciferous mica- 
schists are termed Cambro-Silurian, because Trenton-Utica grap- 
tolites occur in them. Various limited outlying patches of 
Upper Silurian fossiliferous rocks rest upon the mica-schists. 
It is easy to connect these belts with their more southern devel- 
opments. Some portions of what we have called Huronian are 
Pre-Cambrian, in the two diverging areas specified above, page 
54. The two bands of argillite supposed to overlie the hydro- 
micas, the one reaching to Barnard and the other to North 
Hartland, are identical with the Cambrian of Ells, and there is 
complete agreement as to the order of succession of all the 
formations named between the two surveys. This argillite 
underlies the Calciferous mica-schist. (5) In this connection it 
is proper to say that recent studies enable me ‘to trace the 
argillite of Bernardston, Mass., past Bellows Falls to East 
Hanover and Orford, and it is to be distinguished from the two 
ranges just named in Vermont, for it overlies the Calciferous, 
and is associated with the latest rocks of the Connecticut Val- 
ley, being perhaps Devonian. I have recently explored a mass 
of it in Littleton, N. H., which appears to overlie the 
Niagara. It was called Cambrian in part in the New Hampshire 
report, because it seemed to be the same with the slates of that 
age further west, while other portions carrying incipient stauro- 
lites and small garnets were denominated Coés slate. (6) A 
study of several areas of hornblende-schist proves that they are 
igneous. (7) The area of the Montalban about the Presidential 
range among the White Mountains proves to be less in amount 
than has been stated. Mts. Adams, Jefferson and even the top 
of Mt. Washington are composed of mica-schists like those 
occurring along the carriage road rather than the true gneisses. 
On Mt. Clinton the mica-schists carry fragments of other rocks 
as if they were an igneous paste carrying inclusions. 
