Notes and Corrections. 



Section- III. No. 6. 



Dr. T. Sterry Hunt. On a Natural System in Mineralogy ; with a Classification of Ka tire SiUcato'. 



-A Supplement to this paper will be printed in the next volun^e of the Transactions, and 

 will embody the corrections and additions wliich appear in the Author's " Mineral Physiology 

 and Physiography," (Boston, 1886.) 



Section IV. No. 1. 

 Sir Wm. Dawson. On Ike Mcsozuic Floras of the Rochj Mountain Region of Canada. 



1. The stream referred to as the " Middle Brancli, North Fork, Old Man River" is tbe same 

 as that elsewhere in the paper styled the " N. W. Branch of the Nortli Fork, Old Man River." 



2. The initials of Mr. Tyrrell of the Geological Survey, given as " R. B.", should be " J. B." 

 o. On page 19, line 1, and in the note on page 20, the thickness of the Fort Pierre and Fox 



Hill groups is stated as being 1,700 feet. The thickness of these formations in the district in 

 question does not exceed 800 feet, though, with respect to the horizon of fossil plants referred 

 to, 400 feet may be added to this for the Upper part of the Belly River beds. 



4. The species Atnelitn Tyrrellii belongs to the Fort Pierre and not to the Laramie. 



5. A recent letter, from Prof W. M. Fontaine of Virginia College, informs me that lie is now 

 studying, and will shortly i.iul.ilislj, a Lower Cretaceous Flora from Virginia whii'li may possibly 

 be as old as the Kootauie beds. He also states that he has reason to believe that some of the 

 leaves usually referred to Podozamites belonged to broad-leaved conifers. I think it likely that 

 those I have described are really cycadaceous ; but in some of the beds there are great num- 

 bers of detached leaflets resembling Podozamites, and which may have been derived from 

 coniferous trees. 



It is to be observed that, in the above paper, the author does not deal specially w ith the 

 questions raised by the Laramie Flora, which he regards as a transition group between the 

 Cretaceous and the Tertiary, the same ground which he occupied on this subject in 1875. 

 Additional material is however accumulating, and it is hoped that the whole Laramie iîora, so 

 far as known, may be dealt with in the course of this year. In the meantime it seems not 

 improbable that if a line of separation can be drawn between the flora of the Upper Cretaceous 

 and the Eocene, it may pass through the Willow Creek series in the middle of the Laramie. 



