with some Notices of American Diatome. — 119 
hundred square yards in extent, which is wholly era up eo the 
siliceous shells of the Bacillaria, §c. in a fossil sta 
This deposit is about a foot below the surface “ys a small j 
bog, immediately at the’ foot of the southern escarpment of the 
hill on which the celebrated Fort Putnam stands. In draining 
this bog, a large ditch was dug, and among the matter thrown 
out, my attention was attracted by a very light, white or clay 
colored substance, which when examined closely in the sun-shine, 
showed BP glimmering linear ‘particles. On submitting it 
ion, by means of a good microscope, I found it to be 
almost aad? composed of fossil: Infusoria, with occasionally: a a 
few fragments of a Diatoma or Fragillaria. 
I have since examined many specimens, taken from different 
and distant parts of the same bog, and have invariably found 
the same siliceous bodies, and in-the same abundance. 
» ‘There can be no doubt that in this place there are several tons 
of the shells of beings so. minute as to be barely visible as brilliant 
specks, when carefully observed in astrong light by the naked 
eye. Hundreds of years must have elapsed before such an accu- 
mulation could have. been-made. 
’ The forms most abundant in this peciouths are vopiesdanted on 
Plate2. Fig. 1, represents one of the Bacillariz, which is appar-. 
ently identical with fossil specimens from Ehrenberg. Fig. 2, 
represents a boat-shaped shell, which like the preceding is marked 
with parallel lines of almost inconceivable fineness. Fig. 3, shows 
a smooth siliceous body whose nature is to me unknown. Fig. 
4, is arough siliceous. body of whose nature I am also ignorant, 
With these occur great quantities- of exceedingly _ 3 ings, 
discs, and smberee see Fig. 11, Plate2.. 
All forms together compose a white or clay colored mass, 
which when dry feels very light, does not effervesce or dissolve 
in acids, and is not Hee by the blow-pipe. I have no doubt 
that this substance will be found abundantly in many peat-bogs, 
and I hope in the next number of this Journal to see the announce- 
ment of its discovery in many ee. From its white color, 
Snes writing the above, I received from my sciontilic friend, O. Mason, Esq., 
President of the Providence page Soviet, a letter from vehncl I take the liberty 
to extract the following. He sa yo fth white sub- 
stance oceasionally esas at hs Sion cof p pr boge have afforded a gorda and 
very curious p which has often occupied my mind. I eould 
