178 



[Jan. 17, 



Hank behind rank, the various aquatic and marsh plants advance into 

 every shallow, building it up to the common level over which the floods 

 pass, adding new sediment, instead of carrying away that already accumu- 

 lated. In this way the land is slowly extending itself, confining the river 

 more and more to its proper channel ; hut this process cannot materially 

 alter the character of the valley, unless aided hy some convulsion of nature 

 Much yet remains to be done on the Lower Ama/.onas, in filling in the 

 details of this imperfect sketch, which will, I trust, be found to be accurate 

 iu the main, and which will serve to show how interesting the region is in 

 itself, and in its relation to the rest of the Continent. Of the Upper Amu- 

 zonas or Marahon region, enough is already known to show its surpassing 

 interest and importance. Between the two, the middle or Solimoes region, 

 is an almost perfect blank, in which future explorers will meet with diffi- 

 culties, even surpassing those presented by the other regions, but will, by 

 well directed efforts, reap results commensurate with the hardihood of the 

 undertaking. 



Stated Meeting, January 17, 1879. 



Present, 11 members. 



Vice-President, Mr. Fraley, in the Chair. 



A letter of acknowledgment was received from the Natural 

 History Society, Emden (100; List). 



Letters of envoy were received from the French Minister 

 of Public Instruction ; and the Meteorological Office, Lon- 

 don, December, 1878. 



A letter of thanks for correspondence was received from 

 the Rev. Stephen D. Peet. 



A letter respecting exchanges was received from Mr. G. 

 W. Ranck, Curator of the Kentucky Historical Society. 



Donations for the Library were received from the Ade- 

 laide Observatory ; M. P. Volpieelli at Rome ; the Geo- 

 graphical Society and Revue Politique at Paris ; the Meteoro- 

 logical Office, and Register, and London Nature; the Bos- 

 ton Natural History Society ; American Journal of Arts and 

 Sciences; Library Journal in New York ; the Franklin In- 

 stitute, College of Pharmacy, Journal of the Medical Sciences, 

 and Medical News in Philadelphia; the American Journal 



