IQ*") The A mericdU (ieoloflist. Septcinber, 1897 
to a temporary channel through lake Simeoe for the drainage of the 
Georgian liaj' while the district to the noi-thvvard was occupied by a lake 
of the glacier. 
Piof. H. F. Osl)orn gave an address on a new region of vertebrate fos- 
sils in the west which he has named the Huerfano. It is in the hori- 
zon of the Lower Eocene and Prof. Osborn has divided it into a lower, 
middle and upper portions. The tirst and second are contemporaneous 
with the Puerco, Green River and Wachsatch, and the third with the 
Bridger beds of the Tertiary. Like others they are the freshwatei- depos- 
its of an ancient lake into which were washed the relics of the sur- 
rounding fauna. The thickness of the shale is 8000 feet and the beds 
overlie the laccolites of Silver mountain and Spanish peaks. The fossils 
of the beds were not described. 
"The Chicago Outlet" was the title of an address by Mr. Frank Leve- 
rett. The substance of Mr. Leverett's contribution, which was recent- 
ly printed by the Chicago Academy of Science was as follows. The 
outlet was the channel of e.scape for the waters of a lake which existed 
during the ice age and for which the name of lake Chicago has been 
proposed. This channel led from the Michigan basin by a double course 
around the site of the present city and is cut chiefly through soft mo- 
rainic and other glacial material, but to a slight extent in the limestone 
r<jck. Mr. Leverett described two stages in the history of lake Chicago, 
marked by distinct beaches. 
Prof. W. N. Rice presented a review of the various theories regarding 
volcanic action and expressed his preference for that which was based 
on the view that the viscid core of the earth was kept solid by pressure 
and that the local relief of this pressure caused liquefaction of the ma- 
terial which was followed by outflow. 
Mr. Parmelee presented a few notes on the minerals of Cripple Creek, 
Col., and spoke particularly of an ore of gold consisting largely of tellu- 
rium which was separated by heat as telluric acid. He showed a small 
but very nearly perfect crystal of this compound. 
A very remarkaVjle coral from the Hippurte limestone of Jamaica was 
described at length with specimens and illustrations by Prof. R. P. 
Whitfield of New York. Barrettia monilifera is a massive form, the 
specimen shown being about 18 inches long by 8 inches in diameter. It 
is calyptrate and the genus has been mistaken by previous writers work- 
ing on less perfect examples for a bivalve mollusc. Full details cannot 
be given here but will appear in the Bulletin of the N. Y. Museum of 
Natural History. 
Two other papers, one on "Ice-jams and their glacial effects," and 
the other on "Carboniferous strata of Michigan," closed the program. 
Few of the foreign geologists were present at Detroit. Prof. Penck of 
Vienna, already mentioned, Prince Kvapotkine from Kent, England, 
and Dr. H. P. Truell from Wicklow, Ireland, were present at several of 
the sessions. 
A joint session of the sections of geology and geograi)hy was held on- 
Wednesday afternoon to hear and discuss, several papers on ancient man 
