268 TRANSACTIONS OF THE [May 18, 
diopside variety in very large crystals), gray amphibole, feld- 
spar, scapolite, phlogopite and tourmaline. The minerals fill 
irregular pockets or form short veins, scattered through impure 
crystalline limestone. The mode of occurrence is similar to 
that at the tourmaline locality, except that the minerals are 
more abundant. The association at once suggests a contact 
zone; but the limestone is the only rock shown in the immediate 
vicinity, there being nothing that could be regarded as an intru- 
sive. Thus, there is afforded one of the localities of most 
doubtful nature, referred to at the outset of the inquiry. The 
minerals are precisely those species that might be expected in a 
contact zone, but no igneous rock is at hand to produce them. 
Were the occurrence an isolated one it would be most difficult 
to account for; and even with the knowledge gained from 
other localities it is only possible to suggest a hypothetical ex- 
planation, for which there is little positive basis. Recalling the 
phenomena shown atthe first-described locality, together with the 
less decisive data of the Pierrepont tourmaline locality, it seems 
possible that the minerals under consideration may have been 
formed by the action of solutions connected with an intrusion that 
now underlies the locality without any exposure at the surface, or 
by one that extended as a sheet above the minerals and has now 
been removed by denudation. 
That this explanation is based entirely upon analogy, using 
the laws of association as a guide, is evident, and its purely 
hypothetical character needs no further accentuation. But the 
locality is far from unique in this respect; indeed it may serve 
as a type of many localities where positive data as to the origin 
of the minerals are lacking, and it is possible to get a clue to 
the solution of the problem only by applying the laws derived 
from a study of more favorable localities. 
An occurrence suggesting two very different explanations is 
on the farm of T. Fitzgerald in Pierrepont. This is another of 
the well-known localities at which much blasting has been done, 
and from which large quantities of minerals have been taken 
out. The association resembles that of the previously- 
described localities, but with fewer species, the minerals being 
pyroxene and scapolite, in large, coarse crystals, together with 
the peristerite variety of albite. Coarse pink calcite encloses 
the other minerals. 
The mineral body occurs upon the contact between crystal- 
line limestone and a rather fine, granulitic pyroxene gneiss. The 
gneiss forms a sheet that has the appearance of being inter- 
bedded, and there is some indication of a gradation between the 
two rocks ; but in neither respect is the evidence entirely satis- 
