192 Cincinnati Society of Natural History. 



Prof. E. D. Cope* called the Judith River Group No. 6 Cretaceous. 

 He showed its conformability with the underlying marine Cretaceous, 

 and gave a section 332 feet in thickness, though its maximum is not 

 less than 500 feet. His section in ascending order is as follows: 



Arenaceous marl (with Dinosauriau bones near the top) .... 125 feet. 



Sandstone, 1st 5 " 



Sandstone 6 " 



Impure lignite 2 " 



Sandstone, 2d 10 



Impure lignite 4 " 



Unio bed •. 30 



Eusty sandstone (with fresh water shells) 25 " 



Arenaceous marl (with petrified wood) 50 " 



Sandstone, 3d 15 



Marl 20 " 



Reddish shale 10 " 



Lignite 5 " 



Shale 7 " 



Black shale and lignite 3| " 



Bed of Ostrea suhfrigonalis 15 " 



Total .332| feet. 



The presence of Dinosauriau s, gar fishes, turtles, Physa, Viviparus 

 and Unio prove the fresh water character of the strata, while the 

 Ostrea indicates a return to brackish water. 



Dr. C. A. Whitef described, from the Judith River Group at Cow 

 Island and Dog creek, a tributar}^ of the Upper .Missouri river, in 

 Montana Territor}^ Unio cryptorhynchus, U. senectus, U. primaevus, 

 Anodonta propatoris^ Bulinus atavics, and Physa cop)ei. 



Prof. F. B. MeekJ; described, from near Laporte, Colorado, Anomia 

 rmtiformis; from East Canon creek, Wasatch Range, Utah, Cucidlcea 

 obliqua, 3Iactra emmonsi; from Cooper creek, Laramie Plains, 

 W3'oming, Axinma ivyomingensis; from Red creek, Uinta Mountains, 

 Utah, Mactra arenaria; from East Canon creek, Utah, Mactra utah-- 

 ensis., TelUna isonema^ T. modesta, Gyrodes dejoressa^ and Anchura 

 fusiformis. 



Prof. C. A. White§ described, from east of Impracticable Ridge, 

 Utah, Ostrea prudentia; from near Pueblo, Colorado, Inoceramus 



•■ Bull U. S. Geo. Sur., Vol. 3., No. 3. 

 f Bull U. S. Geo. Sur., Vol. 3., No. 3. 

 t U. S. Geo. Expl., 40th parallel. 

 ? Wheeler's Sur. W. 100th Mer., Vol. 4. 



