1896. ] NEW YORK ACADEMY OF SCIENCES. 261 
vein formation. The large masses of hematite with minor car- 
bonates, quartz, millerite, etc., are suggestive of extensive 
metasomatic action. The widely diffused phlogophite, graphite, 
tremolite, etc., in the crystalline limestone are evidently a prod- 
uct of regional metamorphism. ‘The beautiful tourmaline, with 
associated quartz, pyroxene and other silicates, may, with some 
probability, be referred to fumarole action. But perhaps the 
most striking association is that found at many localities, and 
involving all or several of the following minerals: pyroxene, 
scapolite, phlogopite, titanite, amphibole, orthoclase, albite, 
wollastonite, graphite, zircon. Of these, the first five are ap- 
parently most common. For such an association as this, con- 
tact metamorphism at once suggests itself as a probable cause. 
But while conclusions drawn from a mere statement of the 
simultaneous occurrence of species have a certain value as in- 
dicating lines of investigation, they can not, of course, be re- 
garded as anything but tentative until tested by field study. 
And, as a matter of fact, while the field relations of some locali- 
ties prove to be precisely what might be predicted from a knowl- 
edge of the occurring minerals, in other cases the relations are 
of a doubtful or even contradictory nature. It is hoped that 
the study of typical and clearly-defined instances of the different 
classes of mineral occurrences may furnish data for the inter- 
pretation of the more uncertain cases, and for, at least, a partial 
formulation of the laws of association as related to origin. For 
the present, the discussion will be limited to the last group of 
minerals referred to above, dealing first with a few typical ex- 
amples and then taking up some of the doubtful cases. 
The chief locality in question is mentioned in Dana’s list, being 
on the Martin farm in Rossie, some two miles north of the vil- 
lage. Blasting has been done here, so that the minerals are well 
shown, forming an irregular mass several yards in diameter. 
The prevailing minerals are pyroxene, phlogopite, scapolite, cal- 
cite and titanite, with minor apatite, tourmaline and quartz. 
The pyroxene is in large crystals, two or three inches in diame- 
ter, of a dark green or black color. The scapolite is also in large 
crystals, with prisms of first and second orders about equally 
developed. The color is generally gray. The composition is 
probably near that of wernerite. The mica is in large, irregular 
masses of a very dark brown or black color. The tourmaline 
is black, and in small crystals not very abundant. The titanite, 
in very small crysfals of a rich cinnamon brown color, is mostly 
deposited upon the other minerals, with the exception of the 
coarse calcite which encloses and fills the cracks between all of 
the others. 
