372 The American Geologist. '^""''' ^'^*^^- 
posits which have hitherto been supposed to be contemporan- 
eous. 
"This conclusion I base largely upon the fauna of the Wy- 
oming beds, which present, in some respects at least, a startling 
resemblance to that of both the Judith River and Belly River 
series. 
"Not only a number of genera, but also a number of spec- 
ies previously described from Montana and now recognized by 
Lambe in the Belly River deposits, occur here in the supposed 
later deposits of Wyoming. It would seem almost incredible 
that so many of these should have persisted unchanged through 
the long interval represented by so many thousand (!!!) feet 
of Fox Hills deposits, to say nothing of the Fort Pierre." 
Dr. Williston also calls attention to the fact that the late 
professor Marsh made no mention of a number of interesting 
fossils from the Laramie of Converse county, Wyoming, which 
must have been known to him, and infers from this that Marsh 
believed them identical with others already described from the 
Judith River beds which he believed of equivalent age. Among 
such forms Williston mentions as occurring in the collections 
from the Converse County Laramie, now in the museums of 
Chicago University and of the University of Kansas, the fol- 
lowing, which he is unable to distinguish either generically or 
specifically from the Judith River and Belly River forms : 
Myledaphiis bipartitns Cope, represented by isolated teeth. 
Accipcnscr (sic) alhertensis Lambe, represented by frag- 
ments of shield. 
Lcpidostens (Lcpidotiis) occidciitalis Leidy, represented by 
detached scutes. 
Crocodihis huniilis Icidy, detached teeth, scutes and isolated 
vertebrae. 
Scaplierpcton tectum Cope, scattered vertebrae and mandib- 
ular fragments. 
Chauipsosariis, Cope, scattered vertebrae. 
Aublysodon cxplanatus Cope, detached teeth. 
Paleoscincus as per Lambe, detached teeth. 
Bacna hatchcri Hay, carapace and plastron. 
With this general statement as to Dr. Williston's views re- 
garding the actual and relative ages of the Lance Creek (Cer- 
atops) beds, Judith River and Belly River beds, let us proceed 
