976- REVIEWS 



One of the chapters of the paper is on the Devonian rocks. From 

 the Devonian beds on the Rio Maecuro Dr. Joao Coelho brought a 

 large number of fossils, which show the existence of beds literally 

 full of mollusks, principally brachiopods, proving the existence of 

 members of the Devonian series more recent than has been supposed 

 to exist there. 



The study of these materials shows the necessity of a study of the 

 stratigraphy of the Amazon region in order to fix the position of these 

 fossiliferous beds and to settle finally the geologic structure of this 

 part of South America. It will be the first important task of the geo- 

 logical section of the Para Museum to give a correct synopsis of these 

 structural features. J. C. Branner. 



The Formatio7i of the Quaternary Deposits of Missouri. By James 

 E. Todd. Reports of the Missouri Geological Survey, Vol. 

 X. State Printer, Jefferson City, 1896. 



This excellent report describes in detail the glacial drift which 

 covers the northern portion of Missouri, treating of it analytically in 

 its various phases, including the forest beds and old soils that are 

 embraced within the drift. This is followed by a description of the 

 loess and its associated deposits; of the terraces and ancient channels, 

 and of the alluvial deposits of the existing streams. Following this 

 exposition of the observed facts, the leading problems that arise from 

 them are taken up and considered in succession. Under this head is 

 discussed the former existence of a barrier between the Missouri and 

 Gasconade rivers, which the author regards as an important factor in 

 explaining the phenomena above that point. The origin of the loess 

 is considered and the conclusion reached that it had a fluvio-lacustrine 

 origin. In considering the erosion of the Missouri River, it is con- 

 cluded that it had unusual facilities for rapid excavation of its channel. 

 A postglacial deformation of the Pleistocene plain is advocated. The 

 method of deposition of the drift is discussed and some modifications 

 of the simple glacial hypothesis suggested. The recent classification 

 of the drift sheets is adopted. The report is closed by a brief, clear 

 sketch of the sequence of events. The discussion is careful and judi- 

 cial in tone. The report is well illustrated with photographic views 

 and profiles and the necessary maps. T. C. C. 



