38 Later Extinct Floras of North America, 



under consideration, proof not only of a wanner climate at the 



far North during the Miocene epoch, but that a part of the 

 plants which tunned the Miocene flora of Europe, actually did 

 travel that road (at least visited all these localities); and in the 

 buried remains of generations which were never to see the 

 promised lam), we have imperishable records of their presence 

 and of the reality of this migration. 



That we cannot, without further study of the facts, assign a 

 CO.U81 for this great change of climate in the northern part of 

 the continent, is no argument against its existence, for the facts 

 are incontrovertible. 



DESCRIPTIONS OF SPECIES. 

 Psilotiuii inea'iiie (n. sp.) 



In the collections made by Dr. Ilayden are several groups 

 and masses of a dichotomously branching plant, which could 

 hardly have been anything else than a Psilotum. The stem and 

 blanches are flattened and smooth, both on the surfaces and 

 sides, and buow no organs of fructification. In size and general 

 appearance this plant may be compared with l\s. complanatum 

 >>\' the Sandwich Islands, but differs from that in having the 

 edges of the leaves smooth, while in the living species they are 

 remotely toothed. We have now but a Bingle Bpecies of 

 /' ilotum growing within the limits of the CTnited States, /'.v. 

 triquetrum of Florida, a more slender plant than this, with tri- 

 angular and toothed branches or lea 



"Formation <//"/ Locality. Miocene strata. Fort Union. 

 (Dr. Eayden.) 



Phragmitei (sp*) 



Anions the plants collected by Dr. Ilayden, from the Miocene 

 beds near Fori I In ion, are numerous fragments of whal seems 

 to be a species of Ph/ragmites. TheBe consist of portions of broad, 



