144 THE NAUTILUS. 



When discussing the Vohitidse in the Wagner Inst. Transactions 

 in 18y0, I stated that I had not attempted to revise the nomen- 

 clature of the group at that time ; but if I had been aware of the 

 serious reformation needed in the accepted nomenclature, 1 should 

 have felt obliged to undertake it without delay. — Wm. H. Dall. 



PUBLICATIONS RECEIVED. 



Loess Papers : The Loess of Nachez, Mississippi ; The Loess 

 and the Lansing Man ; Loess and the Iowan Drift ; Evidences (?) 

 of Water-deposition of Loess. By B. Shimek {Bull. Lab. Nat. 

 Hist. Iowa State University, V., no. 4). The question of the genesis 

 of the loess of the Mississippi Valley has interested two generations 

 of geologists. Until quite recently the great majority of American 

 writers, and among them Prof. Shimek himself, ascribed its deposition 

 to the action of water. Later studies by Shimek, covering ex- 

 posures over practically the whole loess area, caused him to advocate 

 the view that our loess is of iEolian origin. This thesis is dis- 

 cussed with great ability, and it is not possible here to give an ade- 

 quate outline of the argument. It is shown that the highest and 

 thickest deposits of loess lie along the larger streams, and their 

 deposition by water would require vast inland lakes, of which there 

 are no traces of shore-lines. The fine and homogeneous deposits 

 containing fragile shells unbroken and unworn, are not such as would 

 be deposited by aqueous action. Moreover, fluviatile shells are ab- 

 sent, the loess fossils being chiefly land shells, and exceptionally 

 those of small pools. A great mass of evidence, geological and 

 faunal, is brought forward to show that the loess is of the nature of 

 an upland dune formation. 



The argument for oeolian origin from the fossil shells will be read 

 with great interest by conchologists. Prof. Shimek's thorough knowl- 

 edge of both the loess and the modern faunas enables him to deal 

 hard blows to those who attempt to defend the aqueous theory on 

 palasontologic grounds. The last essay of the series is a damaging 

 critique of the papers of Prof. G. Frederick Wright and Luella A. 

 Owen. There are fourteen excellent plates, two representing fossil 

 land shells of the Nachez loess. 



This brochure contains the most complete and authoritative exposi- 

 tion of the subject of loess formation in the English language, and 

 will be invaluable to all students of the loess and its fossils. — H. A. P. 



