MUSEUM OF COMPARATIVE ZOOLOGY, 41 
Wherever the direct contact was found, however, namely, in the southeast 
corner of the town of Lebanon, and at Humphrey’s Quarry, in the southern 
part of the town of Pittsfield, the folia of the mica schist were found to lie in 
planes parallel to the planes of bedding of the limestone, and in the latter 
locality the limestone and mica schist were distinctly interbedded. There is 
every appearance, throughout the region, of the different formations being con- 
formable with each other, and they are so represented in the section below the 
large map. 
In all parts of the region where good observatiuus could be taken, with one 
exception, the rocks dip steeply in directions between E. S. E. and east. There 
are irregular variations of the dip ranging from 30° to 80° in different parts of 
the same formation. The average dip along the section is about 60°, and, pro- 
vided there were no faults or folds in the region, the beds would have a thick- 
ness of 34,000 feet, or about 64 miles, An exception to the almost universal 
easterly dip has been alluded to. This exception occurs in the vicinity of Mr. H. 
Salmon’s house, near the northwestern border of the Richmond limestone area. 
In a small ravine just west of Mr. Salmon's is to be seen an anticlinal arch in 
the limestone, the axis running X N. E., and a quarter of a mile northeast of 
Mr, Salmon's is a portion of another anticlinal, the axis of which is parallel 
to, ahd about a quarter of a mile east of that of the former. 
According to Professor J. D. Dana (* Geology of Vermont and Berkshire," 
Amer, Jour, Science, July to October, 1877) the limestones of Berkshire 
County lie in extremely eroded anticlinals, while the schists occur in. the shape 
of less eroded synclinals which rest conformably on the limestone. Different 
degrees of flexure in the anticlinals and synclinals are to be observed in different 
localities throughout the county, in some of them the flexure being so extreme 
that the strata are folded double, with the planes of the folds dipping to the 
east, the strata of those portions of the folds which have not been removed by 
denudation presenting the appearance of interstratification. 
So far as the facts observed in the region of the Richmond Boulder Trains 
are concerned, it seems that the structural relations of that region may be ex- 
plained in accordance with Professor Dana’s views. The three great masses of 
schist in the three parallel ranges lie in extremely flexed synclinals, which are 
contained between the anticlinal folds of the three great limestone belts. The 
limestone belts are continuous with each other beneath the ridges of schist, and 
the different masses of schist were once a continuous stratum overlying the 
limestone, but have become separated through the loss by denudation of the 
anticlinal portions of their folds. 
According to Professor Dana,* the Berkshire limestones are part of the con- 
tinuous belt of that rock which extends through the western part of Connecti- 
cut, Massachusetts, and Vermont, the portion in Vermont being called the 
Eolian limestone. The limestone in Massachusetts is of the same age as the 
Eolian limestone in Vermont. From the fossils discovered in the Eolian lime- 
* Amer. Jour. Science, Vol; XIV., 1877, p. 37. 
