1897.] Proceedings of Scientific Societies. 265 
Eleventh Annual Session of the Iowa Academy of Sci- 
ences.—The Iowa Academy in its eleventh annual session at Des ° 
Moines, Dec. 29th and 30th, 1896 enjoyed one of its most profitable 
sessions. The papers presented were as follows. : 
Prof. S. Calvin, “ The State Quarry Limestone,” discussed a series of 
limestone ledges in Johnson Co., Iowa, which are of Devonian(?) age 
and consist of comminuted parts of brachiopods, crinoids, etc., some of 
them deserving to rank as a brachiopod coquina. Its unconformability 
on the Cedar Valley limestone shows an erosion period not hitherto 
suspected in the Devonian and is evidently one of long duration. The 
fauna of the’formation included the Devonian Ptyctodus and the sub- 
carboniferous Psephodes among the rich fish remains and also brachio- 
` pods showing affinities to the carboniferous forms. 
©. R. Keyes, “ Stages of the DesMoines or Chiey coal-bearing series 
of the Kansas and southwest Missouri and their equivalents in Iowa,” 
also, in conjunction with R. R. Rowley (read by title), “ Vertical 
Range of Fossils at Louisiana.” 
A. G.j{Leonard, “Natural Gas in the Drift of Iowa” enumerates 
localities where natural gas occurs in the state and discusses its origin. 
Of the coal measures shales and the vegetable remains in the drift as 
possible sources the author concluded that for the Iowa localities the 
latter is the probable one. 
J. L. Tilton, “ Results of Recent Geological work in Madison Co.” 
describes the"geological formations of the county and discusses partic- 
ularly the relation of preglacial to present drainage system. 
G. E. Finch, “A Drift Section at Oelwein” described minutely an 
exposure recently brought to light in a railroad cut showing three dis- 
tinct till sheets. 
S. G. Beyer, “Evidence of a Sub-Aftonian Drift in Northeastern 
Towa.” Deduces from evidence at Oelwein, Albion and other points 
the extension of the Sub-Aftonian to this portion of the state. 
T. H. Macbride, “The Botany of a Pre-Kansan Peat-bed ” described 
recognizable plants occurring in the drift section exposed at Oelwein. 
B. Shimek, “ Observations on the Surface Deposits of Iowa ” gave 
additional observations in support of his view presented at the last 
annual meeting of the Academy that the loess formation of western 
Towa were of aeolian origin. : 
The same author in “The Flora of the Sioux Quartzite in Iowa,” 
listed the species observed on this formation and discussed their relation 
to the flora of the other parts of the state, ‘‘ Notes on the Aquatic 
Plants of Northern Iowa” also by the same author was devoted mainly 
to the flowering species occurring in ponds and lakes. 
