448 THE CANADIAN NATURALIST. [Vol. ix. 



materia], much better adapted to tlieir preservation than the soft 

 ihalea in which the fossils of this formation usually occur. 



One of the most remarkable leaves in the collection is that of 

 % magnificent Platanus or Sycamore, a foot or more in length 

 and of proportionate width. It is identical with P. Noh'dis of 

 Newberry, from the Tertiary beds of Fort Clarke on the upper 

 Missouri. Mr. Selwyn's specimens, which show the venation 

 and margin very perfectly, justify Newberry's reference of the 

 leaf to the genus Platanus. They also show, in one specimen, a 

 feature not preserved in those previously found, namely the 

 presence of two short basilar lobes extending backward on the 

 petiole. Each of these is about an inch in length, pointed at 

 the extremity, and with one large lateral tooth, and two nerves, 

 one extending to the point, the other terminating in the tooth. 



Another interesting leaf represents a species of Sassafras, a 

 genus not hitherto found in our Lignite Tertiary, though repre- 

 sented in the Cretaceous and in modern times. The species has 

 been dedicated to Mr. Selwyn, being apparently new. The col- 

 lection also includes several Poplars, as Populus arctica, Heer, 

 P. cuneata, Newberry, and P. acerifoUa, Newberry, a Hazel 

 and a chestnut-leaved Oak, apparently a new species. There are 

 also some interesting coniferous trees, as Sequoia Langsdorjii, 

 an ally of the giant trees of California, Taxodium Occidentale, 

 of Newberry, and Taxites Olrikl of Heer. 



The flora indicated is, on the whole, similar to that of the 

 Porcupine Creek group of Dr. G. M. Dawson's Eeport on the 

 forty-ninth parallel, that of the Lignitic area of the Mackenzie 

 River, described by Heer as Miocene, that of the Fort Union 

 group of Newberry, and of the Carbon group of Lesquereux, — 

 formations variously regarded as Eocene or Lower Miocene, and 

 very widely distributed over the western plains. 



These plants will be fully described in a forthcoming report of 

 the Geological Survey, where their affinities and geological rela- 

 tions will be discussed. 



Pablished Dec. 29, 1880. 



