Tufaceous Lacustrine Formation of Syracuse, Onondaga 
County, New York. 
My attention was attracted, some years since, on my 
way to Niagara, when passing through the canal, which 
cuts the district of country a few miles east of Syracuse, 
in the state of New York, by a level area of some miles in 
extent. On descending from the boat at the locks, I 
found the substratum, which lined the side of the canal, 
to consist of a calcareous marl of a whitish colour, border- 
ing on that of ashes, friable, and rather soft to the touch.* 
Numerous perfect specimens of the genera Lymnea, Physa, 
Planorbis, Paludina and Ancylus were obtained, all being 
analagous to the species inhabiting, at this time, the fresh 
waters of that region: it was evident that the deposit was 
caused by the drainage of a lake. The specimens were 
found to be completely bleached, and were generally in an 
unbroken state. It has been a matter of regret to me, that 
circumstances did not permit me to make a more minute 
investigation of this interesting deposit, which must be 
considered as a true tufaceous lacustrine deposit. I crossed 
it on a line, east and west, of about two miles, but its 
width and depth I could not ascertain. 
* A subsequent analysis, by Professor Vanuxem, proved it to be nearly 
pure carbonate of lime. 
