Geology and Mineralogy. 157 



No. 144, The Moraines of the Missouri Coteau and their At- 

 tendant Deposits, by J. E. Todd, has 71 pages and 21 plates. 

 The paper includes a map of the glacial phenomena in parts of 

 North and South Dakotas, and numerous illustrations of the three 

 moraines and other various attendant deposits in that portion of 

 the great terminal moraine belt. 



The following folios have been issued : — 



No. 28, Piedmont, Maryland and West Virginia, latitude 

 39° to 39° 30", longitude 79° to 79° 30", by N. H. Darton and 

 J. A. Taff. 



No. 30, Yellowstone National Park, Wyoming, embracing 

 four sheets, Gallatin, Canyon, Shoshone and Lake, on the scale of 

 TgrVoT' by Arnold Hague, J. P. Iddings and W. H. Weed. 



No. 32, Franklin, Virginia and West Virginia, latitude 38° 

 30" to 39°, longitude 79° to 79° 30", by N. H. Darton. 



The Geological Survey has already issued 166 topographic 

 sheets, of which 27 have been issued since February 1st. By Act 

 of Congress, these have recently been placed on sale at 5 cents 

 apiece, or $2.00 a hundred copies. J. s. d. 



2. The Pleistocene Features and Deposits of the Chicago 

 Area ; by Frank Leverett, U. S. Geol. Survey. (Bull. No. II, 

 Geol. and Nat. Hist. Survey of the Chicago Acad. Sciences), pp. 

 1-87, May, 1897. — Mr. Leverett's minute knowledge of the sur- 

 face features of Illinois and neighboring States gives special value 

 to this detailed analysis of the Pleistocene deposits in relation to 

 ancient glacial phenomena. 



In his classification of the drift sheets, as marks of chronology, 

 he follows and amplifies the outline of Prof. Chamberlin, already 

 published. He recognizes fifteen stages and substages in the 

 glacial history of the region, as follows: — 



" Outline of the drift sheets and intervals. 



1. Oldest recognized drift sheet — the Albertan of Dawson. 



2. First, or Aftonian, interval of recession or deglaciation. 



3. Kansan drift sheet of the Iowa geologists. 



4. Second interval of recession or deglaciation. 



5. Illinoian drift sheet. 



6. Third, or preloessial, interval of recession or deglaciation. 



7. Iowan drift sheet and main loess deposit. 



8. Fourth, or post-loessial, interval of recession or deglaciation. 



9. Early Wisconsin drift sheets. 



Substage 1. Shelby ville morainic system. 

 Substage 2. Champaign morainic system. 

 Substage 3. Bloomington morainic system. 

 Substage 4. Marseilles morainic system. 



10. Fifth interval of recession, shown by shifting of ice lobes. 



11. Late Wisconsin drift sheets. 



Substage 1. Great bowlder belts and accompanying 



moraines. 

 Substage 2. Valparaiso morainic system. 

 Substage 3. Lake-border morainic system. 



