136 The A)iuric(in Geologist. Fubruary, i89^ 
It is possible that one meeting' a year will be held away from. 
Minneapolis, the home of the Academy. On Dec. 28, 29 and 
30, meetings in celebration of the twenty-fifth anniversary of 
the Academy were held, at which twenty papers were pre- 
sented. Among these the following pertained to geology: 
"On a little known larviform crinoid from the lower Paleozoic, and 
comparison with the living Anted'on," by F. W. Sardeson, who dis- 
cussed more particvilarly the origin of the centro-dorsal plate of Ante- 
don, tracing it apparently to three, five and six infrabasal phites, respec- 
tively, in Paleozoic crinoids. 
"The glacial lake Agassiz," by Warren Upham. The facts pre- 
sented are found in the author's detailed report on this subject (Mon. 
25 of the U. S. Geological Survey.) 
"Volcanic fragmental rocks at Taylors Falls, Minnesota," by C. 
B. Berkey. This subject is discussed in an article by the author in the 
December number of this journal. 
"The recession of the glacier from the Lake Superior region," by 
A. H. Elftman. The substance of this paper can be found in the author's 
article in this number of this journal. 
"Significance of the fragmental eruptive debris at Taylors Falls," 
by N. H. Winchell. The author regards this eruptive debris as in 
the main an oceanic deposit, forming, in part at least, a true basal con- 
glomerate. Thus the diabase flows at Taylors Falls are separated into 
two parts by an interval of erosion followed by one of oceanic deposi- 
tion. This unconformity and the basal conglomerate are correlated with 
similar phenomena in the Lake Superior region which enable us to 
separate the Keweenawan eruptives into a lower (Norian) and an upper 
scries. 
"Field notes in New Mexico geology," by C. L. Herrick. Some 
of the more important and interesting points in the geology of this 
district were discussed and especial attention was called to points which 
offered promising fields for investigation. 
"The drift in southwestern Minnesota and northwestern Iowa," by 
H. F. Bain. Detailed observations in Plymouth county, Iowa, and 
the surrounding districts, showing the presence of several till, gravel 
and loess deposits, were given and the following prehminary interpre- 
tation was presented: (i) Kansan drift; (2) lowan drift; (3) high level 
gravels connected with Wisconsin moraines; (4) erosion of river 
valleys; (5) sheet loess; (6) Anadonta terrace (?); (7) Missouri River 
loess proper; (8) Later terraces in the loess; (9) Wisconsin gravel trains 
proper. 
"The end of the ice age in Minnesota," by Warren Upham. The 
author presented the main facts of the ice retreat across the state, 
dwelling chiefly on the series of terminal moraines and the larger glacial 
lakes. Of the latter the two lakes in the Minnesota River valley were 
especially discussed. 
"Certain resemblances between the Archean in iMinnesota and in 
Finland," by N. H. Winchell. The resemblances between the Archean 
of these two localities both in sequence of events and in lithology, were 
shov\'n to be comparatively close and the Minnesota series was more 
especially discussed. Tlie sequence in this state is as follows, beginning 
with the most recent: (i) eruptive granite, at Snowbank lake and on 
the Giants range; (2) Upper Keewatin sediments, separated by an 
unconformity from (3) eruptive granite, at Saganaga lake; (4) Lower 
Keewatin or Kawishiwin sediments and contemporary eruptives; the 
rocks of this age consist very largely of "greenstones" most of whicli 
the author regards as water deposited fragmental volcanic debris. 
