546 lI.ul.'A (»!■ Tin: I.ARAMIK (iKori". 



The locality ou Clear Creek, fifteen miles above Glendive and about 

 three miles back from the river, yielded the largest quantity of fossil 

 ])lants, but the flora was more uniform than that of other ])()ints and 

 consisted chiefly of Viburnum leaves, which seemed when collected to 

 belong almost entirely to one species, but upon closer study they prove 

 to vary considerably and embrace a number of distinct forms. Tiie 

 other kinds of plants, too, which in comparison seemed very few and 

 meager, prove, when separated from the Viburnum leaves and care- 

 fully studied, to be quite numerous and varied. Very large and some 

 quite i)erfect leaves of I'Jatanus nobilis, and of the species that possesses 

 the remarkable basal lobe (P. ba.silobata. Plates XLII and XLIII), 

 occurred here, as well as Ulmus leaves, Equisetum tubers, and Legu- 

 minosites fruits. In intimate connection with the abundant Viburnum 

 leaves, and not always easy to distinguish from E(inisetum and Legu- 

 minosites, there were scattered through the shales, always in single 

 detached form, many ovate or elliptical lanceolate fruits, with deep 

 longitudinal furrows (Plate LXII, Figs. 2-G), which, upon careful com- 

 parison, I am convinced are the seeds of the Viburnum. This fact 

 would not possess so great iuiportance were it not that certain leaves 

 apparently identical with the most abundant kind found at Clear Creek 

 had been previously collected from the Fort Union group and referred 

 to a different genus. The discovery of these fruits in such immediate 

 relation to the leaves confirms in a very satisfactory manner the con- 

 clusion which 1 had previouslj' reached and expressed that the leaves 

 published by Dr. Newberry as Tilia antiqiia belonged really to the 

 genus Viburnum. 



Most of the plants collected on Clear t!reek came from a single stra- 

 tum about three feet in thickness, which could be traced for long dis- 

 tances along the clifl' on the left bank of the creek valley and within 

 from twenty to fifty feet of its summit. The rocks consist of a limestone 

 shale which is so argillaceous as almost to deserve the name of marl, 

 slightly ferruginous, light gray, and very compact. The layers are quite 

 thick, sometimes almost massive, so that very heavy sj)ecimens had to 

 be transported ; but at some jjoints a true compact marl occurs, which 

 breaks with ease in both directions and Las a couchoidal fracture. 



Some nine miles farther up the broad valley of Clear Creek occur some 

 elevated ledges, which were visited. On the top of an isolated butte in 

 this locality a bed of compact marl of very friable character was found, 

 contaiiung leaf impressions. This florula was entirely different from 

 that of the locality farther down, and in fact from any other met with 

 on the Yellowstone. The impressions were very clear, but it was ditti- 

 cult to obtain entire leaves, owing to the ease with which the rock 

 would break across the plane of stratification. It was here that were 

 found the very remarkable digitate Aralia-like leaves figured below 

 (Plate XLVIir, Figs. 10-12, Plate XLIX, Fig. 1). Some of the finest 

 specimens of Corylus also came from this bed, and a peculiar fucoid {)Spi- 



