PROSSER. | Cretaceous.—The Dakota Sundstone. IQs 
considered typical Dakota and as of probably Upper Cretaceous 
age. If this supposition be true then the Mentor beds or Lower Cre- 
taceous will correspond approximately with those beds which Meek 
and Hayden thought at first belonged in the Triassic or Jurassic. 
On the accompanying geclogical map the Mentor beds and the 
higher Dakota are mapped as belonging to the “Dakota,” using that 
naine in the sense in which it had formerly been used for the lower 
subdivision of the Upper Cretaceous of central Kansas. This is 
done because at present it is not possible to indicate the line of divi- 
sion between the Mentor and the Dakota formations of central Kan- 
sas, and not with the idea that all of the so-called Dakota group 
belongs in the same formation. ‘The above remarks are intended to 
call attention to a region which promises important results as the 
reward of careful stratigraphical and paleontological study. 
REFERENCES TO DESCRIPTIONS OF THE MENTOR FAUNA. 
The earliest published reference to the Mentor fossils is appar- 
ently that of Dr. John L. Le Conte in 1868. Doctor Le Conte accom- 
panied the surveying party for the extension of the Union Pacific 
railway from Salina westward in 1867 and he reported fossils from 
the Dakota group stating that “near the crossing of Spring creek, 
about a quarter of a mile south of the road, ‘this rock abounds in 
fossils.” The specimens were sent to Mr. Conrad who reported 
fourteen species, ‘‘all of which seem to be new,” and the generic 
names were given in Doctor Le Conte’s Notes. In a foot note Doctor 
Le Conte states on the authority of Mr. Meek that Professor Mudge 
had procured specimens at the same locality.! 
From a paper read by Professor Mudge before the fourth meeting 
of the Kansas Academy of Science, in 1871, it would appear that 
he first found these fossils in 1868, for he said “Three years ago, 
passing from Salina to Harper, when near what is now the town of 
Bavaria, we picked up in the road some marine fossils. Tracing 
the specimens to the top of an adjoining hill, we found a few acres 
covered with a stratum not over two feet in thickness, rich in small 
1 Notes on the Geology of the Survey for the extension of the Union Pacific 
railway, Philadelphia, Feb. 1868, p. 7. 
alls} 
