544 A. C. PEALE 
Hills sandstones and overlying Judith River beds. This fault-line 
was afterward crossed twelve miles to the eastward near the cross- 
ing of Dog Creek. The second fault-line parallel to this one is 
exactly like the first, but the third one, a few miles south of Judith 
Landing, is a block fault of Fox Hills sandstones with a steep dip 
on the southwest side. From Judith Landing a trip up Dog Creek 
for about three miles above its mouth was taken to the point visited 
by Stanton and Hatcher and here another fault similar to those 
just referred to was seen showing, not only on Dog Creek, but 
extending across to the north side of the Missouri River. Lack of 
time prevented a tracing of these lines, and also precluded the close 
examination of the complicated conditions shown on Dog Creek. 
That the structure is complicated is shown by the following 
conditions. In Plate 2, opposite p. 36, of Bulletin No. 257 of the 
Geological Survey is shown a cliff of sandstone referred by Dr. 
Stanton to the Upper Eagle, which was found by him to be very 
fossiliferous, containing the following forms: Cardium speciosum, 
Tellina montanensis, Baroda sp., Callista sp. Cf. C. deweyt, Mactra 
alta, Mactra formosa, Lunatia subcrassa. ‘This cliff was visited by 
us in July, rorr, and in horizontal beds lying below this cliff the 
following vertebrate remains were collected: Champsosaurus ver- 
tebrae, carnivorous dinosaur tooth, Paleoscincus tooth, Crocodile 
teeth, Brachychampsa (?) tooth, ganoid fish remains, and shark’s 
teeth. These were identified by Mr. C. W. Gilmore of the U.S, 
National Museum, who says: “‘All of these forms may be found 
either in Judith River or the Lance formation with the possible 
exception of Brachychampsa, which at this time has been recog- 
nized only at Hell Creek and in the Ceratops beds of Wyoming.” 
In the same series of beds 400 feet higher the following were 
found: carnivorous dinosaur tooth, a small ceratopsian tooth, 
Trachodon tooth, a turtle (not determinable), a crocodile (probably 
Leidyosuchus) and remains of a ganoid fish and shark’s teeth. 
Below the lower of these two fossiliferous beds (both of which are 
regarded as of Judith River age) in beds standing almost on end 
the following invertebrates were obtained, viz., Avicula nebrascana 
E.&S., Tancredia americana M.&H., Tellina equilateralis M.&H., 
Mactra sp., Lunatia subcrassa M.&H., Cardium speciosum M.&H., 
