Winchell.] 'J^'^ [May 6, 1870. 



Stated Meeting, May 20, 1870. 



Present, ten members. 



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



A letter accepting membership was received from Maj. E. 

 E. Williamson, dated San Francisco, May 10th, 1870. 



A letter respecting the Bjington MSS. was received from 

 Prof. Jos. Henry, Sec'y Smithsonian Institute, Washington, 

 D. C, May 16th'. 



Donations for the Library were received from the Academies 

 at Turin, Berlin and Boston ; the Annales des Mines, and 

 Nature; the R. Astronomical Society; Essex Institute; Bos- 

 ton Public Library; Silliman's Journal ; American Museum 

 of Natural History in New York, and Dr. Wm. Duncan, of 

 Savannah. 



The death of Dr. Jas. Y. Simpson, of Edinburgh, was an- 

 nounced by the Secretary. 



ON THE GEOLOGICAL AGE AND EQUIVALENTS OF THE 

 MARSHALL GROUP. 



By Prop. A. Winchell, 

 Director of the Geological Survey of Michigan.. 



PartII.1'2 



IV. Present State of our Paleontological Knowledge. 



I come now to the most important and most interesting branch of this 

 investigation. In order that others may be placed in full possession of all 



112 For Part I of this paper, see Proceedings American Philosophical Society, vol xi-, p, 57 (March 

 5, 1S69). Both Parts of the paper were presented to the Chicago meeting of the American Asso- 

 ciation for the Advancement of Science, August H, 1868. It was not offered for publication in 

 the Proceedings in consequence of its length. It was reported, however, in the Chicago news- 

 papers, and the chief points were briefly-stated in the American Naturnllst for October, 1868, p. i'lS. 

 Parti, was published in these " Proceedings" without alteration; and Part II., as here presented, 

 is unchanged, except in the omission of some detailed lists of fossils, and in the addition of a few 

 remarks based on late discoveries in Tennessee and Pennsylvania, and which have been made 

 public in these Proceedings, vol. xi., p. 245, etc. 



