JUNE 6, 1884.] 
plentifully found. Muncy, Penn., where Mr. Rau 
found his specimens, is on the banks of the Susque- 
hanna, and no doubt shell-fish were caught and eaten 
there as at Tottenville; but this explanation of the 
use of the hammerstones does not seem to be insisted 
upon by him. The Tottenville specimens are made 
of such soft stone that one can hardly imagine any 
other use to which they could be put. The number of 
net-sinkers in use must have been immense, as even 
at the present time, upon the surface of the ground, 
they may be picked up in considerable number. One 
day, in about half an hour, fourteen were found. 
The extent of these shell-heaps can only be computed 
in acres. —— Mr. George F. Kunz of New York pre- 
sented a stone head found near Clifton, Staten Island, 
about two hundred feet east of the railroad just above 
the Fingerboard Road, in a low swamp filled with the 
roots of the swamp-oak. A rustic-basket worker, 
named James Clark, came upon the stone head while 
digging up the roots of a high huckleberry-bush, at 
least ten years of age, growing at the edge of the 
swamp. The soil is a compact, light creamy brown, 
sandy clay, in which a stone like this could be buried 
for an age without much disintegration. When strik- 
ing in his pick, at a depth of from twelve to eighteen 
inches, he turned up the head, his pick striking and 
indenting the chin. The material of which it was 
formed is a brown sandstone, apparently more com- 
pact than the common New-Jersey sandstone, and 
composed almost entirely of grains of quartz, with 
an occasional small pebble. The weight of the head 
is about eight pounds, its height seven inches, and 
it measures four inches through the cheeks, six inches 
from the tip of the nose through to the back of the 
head, and an inch and seven-eighths across the nos- 
trils. ‘The eyes are an inch and a quarter long, and 
five-eighths of an inch wide; they are raised in the cen- 
tres, and have a groove running around close to the 
lids. A round hole a fifth of an inch deep had been 
drilled in the lower part of the nose, in the space be- 
tween the two nostrils, evidently designed for a nose 
ornament, and both nostrils were hollowed out. The 
cheeks, in their lower part, are sunken in a very curi- 
ous manner, causing the cheek-bones to stand up 
very high. The forehead is low, and retreats at an 
angle of sixty degrees. A trace of what had been or 
was to be the ear is perceptible on the right side. The 
back and upper parts of the head are almost entirely 
rough and unworked, as if it had never been finished, 
or was originally a part of some figure. The surface 
is rough and slightly weathered ; the cheeks, forehead, 
and chin having single grains of sand apparently 
raised above the surface, as if by age and exposure. 
The discoverer, in cleaning it, had scraped the eyes 
and beneath the nose with a nail, and his shovel had 
formed a groove in one of the cheeks, — all of which 
scratches or marks have a very different appearance 
from the general surface, and are plainly recent. The 
style is Mexican, or still more resembles Aztec work. 
Minnesota academy of natural sciences, Minneapolis, 
May 6.— Mr. Warren Upham described three re- 
markable chains or series of lakes observed in Mar- 
SCIENCE. 695 
tin county, Minn., during his examination of that 
region as assistant on the state geological survey. 
These are familiarly known as the east, central, and 
west chains of lakes. The east chain extends twelve 
miles from north to south, and includes nine lakes, 
which vary from a half-mile to two miles in length. 
About five miles farther west, the central chain of 
lakes, parallel with the foregoing, reaches about 
twenty miles in an almost perfectly straight north to 
south course, including nineteen lakes of similar size 
with those of the east chain. The west chain is some 
thirty-five miles long, and is made up of about thirty 
lakes. Its course is south-south-east, beginning at 
Mountain Lake in Cottonwood county, and extending 
to Tuttless Lake on the line between Martin county 
and Iowa. The surface of this region is everywhere 
a prairie of unmodified glacial drift or till, with no 
considerable deposits of gravel and sand. Its contour 
is moderately undulating, averaging twenty-five to 
forty feet above the lakes, the shores of which rise 
to this height in steep banks or bluffs. No other lakes 
arranged in such series have been observed, either 
in this state or elsewhere. ‘The explanation of their 
origin which seems most probable is, that they mark 
interglacial avenues of drainage, occupying portions 
of valleys that were excavated in the till, after ice had 
long covered this region, and had deposited most of 
the drift-sheet, but before the last glacial epoch, 
which again enveloped this area beneath a lobe of 
the continental glacier, partially filling these valleys, 
and leaving along their courses the present chains of 
lakes, —— Mr. Upham also briefly described the belts 
of knolly and hilly drift, which have been traced 
through Minnesota by the geological survey. Nearly 
all of these belts are believed to be terminal or mar- 
ginal moraines, accumulated along the boundaries of 
the ice-sheet of the last glacial epoch, as moraines 
are formed at the end and along the sides of alpine 
glaciers. The outermost morainic belt, running in a 
looped course across Wisconsin, Minnesota, lowa, 
and Dakota, marks the farthest limits of this ice; 
and other belts of such drift accumulations, found at 
various distances back from this, mark stages where 
the ice halted in its departure. These drift hills and 
knolls are finely developed on the Coteau des Prairies, 
in south-western Minnesota and eastern Dakota, as 
also on the Coteau du Missouri, farther west. They 
surround Lake Minnetonka, and reach to the west 
edge of Minneapolis; they are also seen between this 
city and St. Paul, and east and north of St. Paul: 
indeed, they cover a considerable fraction of the 
whole state. From Lake Minnetonka a broad belt of 
morainic drift stretches a hundred and twenty-five 
miles north-west to the Leaf Hills, where the most 
massive development of this formation within the 
state is found, its highest elevations being from one 
hundred to three hundred and fifty feet above the 
general level. The outermost belt of these drift-hills 
has been named the Altamont moraine. No less 
than ten other morainic belts are distinguishable in 
Minnesota, showing successive stages in the recession 
of the ice-sheet. These moraines have been named 
from localities where they are conspicuously ex- 
