140 STANTON & KNOWLTON — LARAMIE AND RELATED FORMATIONS. 



Montana formation of the Rocky Mountain region, but a few of them are 

 worthy of special notice. Pachydiscus cow/plexus (H. and M.), which has 

 hitherto been known from a few immature specimens, is here not rare, 

 and attains a diameter of six or eight inches.* At least two other species 

 not hitherto reported from the northwest. Legumen planulatum and An- 

 chura rostrata, are common in the Ripley beds of Alabama, Mississippi, 

 and Texas, and the undescribed Trigonia is closely related to T. eufalen- 

 sis, also from the Ripley. The Legumen is apparently congeneric with 

 Meek's Baroda ivyomingensis. New collections are thus gradually increas-* 

 ing the number of forms common to the Ripley and Montana formations, 

 although the specific differences between these two presumably contem- 

 poraneous faunas are still so numerous that we must assume either con- 

 siderable climatic differences or partial isolation of the two areas of 

 deposition. 



Fossil plants were obtained on the Laramie plains at three other locali- 

 ties where the stratigraphic position is not so plainly evident as at the 

 localities already mentioned. One of these is near Dunn's ranch on 

 Laramie river, six miles east of Harpers, where the following species were 

 collected : 



Myrica torreyi, Lx. Celastrus, n. sp. 



Quercus acrodon, Lx. Salix sp. 



Ficus planicostata, Lx. Spathites sp. . 



It is almost certain that this locality is very near the coal and plant 

 bearing horizon already discussed, yet none of the plants are common 

 to the two localities. 



Near the old stage road on the north fork of Dutton creek, between 

 Rock and Cooper creeks, there is a small coal bed that has been mined 

 to some extent for local use. It is probably the one spoken of as the 

 " Cooper Creek Coal " in the reports cited on page 137. The shale over- 

 lying the coal and the still higher sandstone both contain fossil plants, 

 among which the following, mostly from the shale, were recognized : 



Aspidium, n. sp. Trapa (?) microphylla, Lx. 



Asplenium, n. sp. Ficus sp. 



Woodwardia, n. sp. Castalia, n. sp. 



Brachyphyllum, n. sp. Asimina eocenica, Lx. 



Sequoia reichenbachi, Gein. Diospyros (?) ficoidea, Lx. 



The evidence afforded by these plants, while somewhat conflicting, 

 tends to place this horizon quite low down in the series, or approximately 

 similar to the plant horizon at Harpers Station. Two of the species 



* Large specimens of this species have been reported from Texas by Cragin. 



