90 0. U. Shepard, Sr.—Mineralogical Contributions. 
Ottawa, Sir William Logan has shown that this immense series 
(his Lower Laurentian), some 20,000 feet in thickness, includes 
four great masses of gneiss ae quartzite, divided by three lime- 
stone formations, and that it is in the uppermost of these, which 
tian) or Huronian series. (See Giimbel on the Laurentian o 
Bavaria, translated and published in the Canadian Naturalist 
for Decem ber, 1866). Comparative studies of this kind should 
not be neglected i in the investigation of our American rocks. 
Montreal, May 10, 1870. 
ART. ceil = Contributions ; by CHARLES UPHAM 
EPARD, Sr. 
1. A new variety (species ?) of Columbite. 
THE Columbites of New England deserve a closer examina- 
tion than they have yet received. Those of New Hampshire, 
Massachusetts and Connecticut may embrace at least two, per- 
haps three, Bestest species. A new locality, recently 
different froin i jshodupiioas of the old one on the farm of Mr 
rainard, as to have to doubts — collectors whether it 
oe belongs. to the Columbite grou 
or my 
he 
single repository, contiguous to the ‘center of the village, "abd 
directly in rear of the house of Mr. Nathaniel Cook, the well 
howl collector and dealer in Haddam minerals. The locality 
was opened by explorers for porcelain stone; but the feldspar 
tao ol too ferruginous, being of a somewhat flesh-red color, 
as led to an abandonment of the enterprise. Although this 
very is a recent one, it is not unlikely that specimens from 
the same spot had previously found their way into cabinets ; 
and may thus have led to some of the discrepancies existing in 
the various disseipiions of the Connecticut columbites. 
The general aspect of the crystals is rather peculiar. Instead 
of flattened prisms, they are nearly all square and often, 
through imperfection, decidedly rhombic. ith the common 
