STRATIGRAPHIC POSITION OF JUDITH RIVER FORMATION 757 
south of the international boundary, especially in Fish Creek south 
of the Musselshell River, and at Willow Creek 12 miles north of 
Musselshell. By no stretch of the imagination, can the beds below 
the Belly River series be taken to represent the Pierre shales, either 
lithologically or paleobotanically. In both the United States and 
Canada, the affinities of the flora are with the Dakota and not with 
the Montana. The faunas, in Canada especially, show a mingling 
of Niobrara and Pierre forms, and although there is a bare possi- 
bility that the upper part of the Belly River series may be of basal 
Montana age, it is more than likely that there is here simply a 
mingling of forms as at the base of the Fox Hills formation, where 
there is a mingling of Pierre forms in the transition from one forma- 
tion to the other. We are therefore fully warranted in concluding, 
as pointed out by Dawson long ago, that the Belly River series is 
of Niobrara age. The Eagle formation as named by Walter H. 
Weed includes about 200 feet of fresh-water sandstones overlying 
the leaden grey marine shales of the Colorado formation. In the 
sandstones plants occur that are similar to those found in the 
Canadian Belly River, which Dr. Knowlton afterward correlated 
with the Dunvegan group of Dr. Dawson as found in Canada. Dr. 
Stanton afterward added to the formation about a hundred feet 
of sandstones, shales, and lignitiferous beds from the upper part of 
which he says he collected marine invertebrates that showed a closer 
relation to the Montana than to the Colorado group. ‘There is a 
possibility that some of the beds may have been wrongly identified ; 
as Dr. Stanton says, ‘‘the formation has often been confused with 
several other horizons.”’ However, the Eagle as originally defined, 
together with some of the immediately underlying calcareous and 
gypsiferous shales, marks the base of the Niobrara formation as 
indicated by the flora of the sandstones. 
Apparently the entire series from the base of the Eagle sand- 
stone to the base of the Pierre shales is a unit representing the 
Canadian Belly River formation, but it may be advisable to restrict 
the name Belly River to the soft badland shales at the summit and 
retain the name Eagle for the basal sandstones and their overlying 
shaly beds and possibly apply some other name (not Claggett) to 
the intervening beds. 
