530 PROCEEDINGS OF NEW YORK MEETING. 



there are forme in the Port Union which have an exceedingly recenl fades, but 1 am 

 very loath to argue from this a Tertiary age, For instance, there are what seem to be 

 the leaves of the identical Bpecies of hazel which grows now in the eastern parts of the 

 United States : yet I hesitate to argue from this thai the formation is necessarily very 

 nt. 



In fact, the material from the Port Union formation which is .-till in my hands 

 (partly for the reason that I was unable to identify it with the published flora of the 



globe, and partly because 1 was unable to publish more at that time) inclines to be- 



> i < ■ \- • • that there would really be, as I then stated, no inconsistency in assigning to the 



Porl I rnion an age as ancient as the closing period of the < !reta< us system. Some of 



the farts I might enumerate here, but this would 1"' perhaps tedious; but Borne of the 

 forms ar irtainly not to be identified with any ofthe genera thai have • n found in the 



-il i>r the living Btate. Such form- cannot be regarded as having geological import- 

 ance in fixing age, yet they go a long way in the direction of Bhowing us that the age 



may be more ancient than has been supposed. Tin; genus Trapa has 1 n found in 



both groups, but I am not thoroughly satisfied that the Bpecies are identical. Ln my 

 anxiety not to multiply Bpecies, I called it by the name given to the form described 

 by Lesquereux from the Point of Rocks beds, though it may prove to be a distinct 

 Bpecies; yet we may never know, from the fact that the material collected by him 

 was inadequate. 1 have collected from the Fort Union bed- specimens of that plant 

 containing entire rosettes of leaves as the}' would lie on the surface of the water, and 

 Bhowing to my mind that it must have belonged to the genus Trapa or a closely re- 

 lated form. The Point of Rocks material contained nothing but isolated leaves — that 

 i- to say. there were no rosettes and there were qo stem imply the form and ner- 

 vation of the leave-. These point to the gen us Trapa, and the probability is that they 

 belong to that genus. 



The evidence afforded by the beds at Black Butte station, where the great saurian was 

 discovered by Professor Cope, is perfectly conclusive of the identity of the age of the 

 beds from which that fossil was taken withthatfrom which the leaves of that particular 



locality were taken. We have at the .National Mu-eiim a Bpecimen of the hone from 



that creature, adhering to the opposite Bide of which is one of the characteristic 



Laramie leave-. I have been on this Spot, and collected other fossil plants from the 



same immediate locality. 



Now, with regard to the error, if error there be, in harmonizing or identifying the 

 Laramie and Fort Union deposits : I suppose the responsibility for this must largely 

 resl upon Dr. White, who has made a very thorough and exhaustive study of the 

 entire region, as he define- it from the standpoint of it- molluacan fauna ; and il Beems 

 to me that hi- identification of the two group- and I have conversed with him very 



freely and very much upon this Bubject, and what I -ay is from memory of the oral 



statements made by him— was in th.' nature of a broad, geological generalization. He, 

 in hi- extensive labors in that field, .-imply came upon the salient fact, that through- 

 out tic larger part ■■( t he region now occupied by the Rocky M> tains there i- abund- 

 ant evidence that there existed at a remote period, somewhere near the closeofthe 

 I or beginning of the Tertiary period, a great land-locked sea, originally 



aewhat salt, later brackish, and Anally nearly fresh ; and that the deposits which 

 were made at tic bottom ofthe -, a are apparently continuous all the way up from the 

 pure marine deposits of the upper Ko\ Hills group to the highest of the Fort Union 

 deposits ; and be even ventures to say he has traced it in -one- places -till higher into 



• la which arc admitted to !»• Tertiary. 



