Persona/ and Scientific .Yen-*. 125 
Recent discoveries of glacial scorings in southeastern Iowa. F. M. 
Fcltz. Stria? bearing S. 79° W., discovered jointly by Messrs. Fultz 
and Leverett, are noted and interpreted as indicating an extension into 
Iowa of the Illinois ice-sheet. 
The Buchanan Gravels: An interglacial deposit in Buchanan county, 
Iowa. Samuel Calwn. (Published in full in this issue of the Amer- 
ican Geologist.) 
The Le Claire limestone. Samuel Calvin. The Niagara formation 
includes three stages: (1) Delaware, (2) Le Claire, (3) Anamosa. The 
Le Claire is not sharply separated from the Delaware but is usually a 
more massive, more completely crystallized dolomite. In the upper lay- 
ers small brachiopods, including Homeospira, Trematospira, Nucleo- 
spira, Rhynchonella, Rhynchotreta, Atrypa and Spirifera, are abun- 
dant. The Le Claire shows remarkable local variations in thickness 
and unique cross-bedding. The assumption that the local variations in 
dip are due to deformation is shown to be untenable. The angle at 
which the beds stand never exceeds that of stable slope for the fine wet 
calcareous material of which they were originally composed. The fau- 
nal and lithological variations follow the individual layers in their ob- 
lique courses. 
Variation in the position of the nodes of the axial segments of the 
pygidium of a species of Encririurus. W.H.Norton. Recently col- 
lected and exceptionally good material shows that the pygidium varies 
too greatly to be of value in the determination of species. 
A theory of the Loess. B. Shimek. From the results of studies upon 
the loess of Iowa and Nebraska, and particularly from a careful collec- 
tion and study of the loess fossils, the author favors the asolian origin 
of the loess and advances strong arguments in its favor. 
Tiro remarkable cephalopods from the upper Paleozoic. C. R. Keyes. 
Read by title. 
Notes on the nature of cone in-cone. C. R. Keyes. Read by title. 
Geological Society of Washington. 
At the 41st meeting of this society, held in Washington, D. 
('., January 22d, two communications were presented, one by 
Mr. Arthur Keith, on the Crystalline Groups of the Southern 
Appalachians, and the other by Prof. Chas. R. Van Hise, of 
the University of Wisconsin and the U. S. Geological Survey, 
on Primary and Secondary Structure and the Forces that Pro- 
duced them. 
Mr. Keith described seven classes of formations, in which 
no evidence of sedimentary origin appeared. These comprised 
gneiss and schist of three types, granite of five types, diorite 
of two types, gabbro of two types, peridotite and pyroxenite 
of five types, basalt and diabase of five types, andesite of two 
types, quartz porphyry and rhyolite of four types. These 
formations, occupy long narrow belts, comparable in extent 
with the sedimentary rocks, and belts of plutonic rocks alter- 
nate with volcanic rocks. Attention was called to the preva- 
lence and attitudes of the schistose planes, due to deformation, 
and to the similar deformation of sediments and crystallines 
in the same area. 
Prof. Van Hise discussed the relations of secondary struc- 
tures to the forces that produced them, and it was concluded 
that there have been two entirely different structures de- 
scribed under the term "cleavage." Following the English 
