FOSSIL FLORA. 673 



8 cm. long and 2 cm. broad, and very much resemble a figure of this species 

 given by Newberry, 1 from the Pacific coast. 



The specimens from the Lamar River are much slenderer, being 7 cm. 

 long and less than 1 cm. broad. Some of them, as fig. 2, are very small and 

 delicate. In nervation the specimens from both localities agree perfectly, 

 as they do with European specimens. 



Habitat: Yellowstone River, one-half mile below mouth of Elk Creek, 

 at base of section; collected by F. H. Knowlton, August 13, 1888. North 

 bank of Lamar River, between Cache and Calfee creeks; collected by F. H. 

 Knowlton, August 21, 1888. 



OSMUNDA AFFINIS Lx. 



PI. LXXX, figs. 4, 5. 

 Osmmula affinis Lx. : Tert. Fl., p. GO, PI. IV, fig. 1. 



The Park collection contains specimens of several detached pinnules 

 that it seems necessary to refer to this species. They are about the same 

 size as Lesquereux's type specimen, but are better, in that they show the 

 bases of the pinnules. 



In the collection of Denver group plants recently worked up there are 

 a number of specimens of this species, some of which are very fine. One 

 in particular, which has been figured for the forthcoming monograph of the 

 Laramie and allied formations, is very large and perfect. It has a long 

 zigzag rachis with numerous sessile pinnules alternately attached. They 

 have a distinctly heart-shaped base, a slightly undulate margin, and a 

 tapering but obtuse apex. In all these particulars, as well as in nervation, 

 the Park specimens agree. The latter are a little shorter than the Denver 

 specimens, and one is a trifle broader, but the differences are unessential. 

 There is no knowing the part of the frond from which they came, and this 

 may readily account for discrepancies. 



Habitat: Southeast side of hill north of Lost Creek, Yellowstone 

 National Park, bed No. 1, about 6,550 feet altitude; collected by F. H. 

 Knowlton, August 5, 1888. 



1 Plates, PI. LXII, fig. 1. [Ined.] 

 MON XXXII, PT II 43 



